[TASK] Update phpstan/phpstan requirement from 1.12.5 to 1.12.6 (#1486)

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/2.0.x/CHANGELOG.md)
- [Commits](https://github.com/phpstan/phpstan/compare/1.12.5...1.12.6)

---
updated-dependencies:
- dependency-name: phpstan/phpstan
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Documentation/Index.rst

@@ -44,7 +44,7 @@ continuous integration.
 
    Introduction
    PHPVersionSupport
-   TestingFramework
+   ReleaseBranchingStrategy
    Environment
    DependencyManager
    Running

Documentation/ReleaseBranchingStrategy.rst

@@ -0,0 +1,65 @@
+.. include:: /Includes.rst.txt
+
+.. _release-branching-strategy:
+
+==============================
+Release and Branching Strategy
+==============================
+
+When maintaining TYPO3 extensions, developers often need to support multiple 
+TYPO3 Long-Term Support (LTS) versions simultaneously. This typically requires 
+a clear release and branching strategy to manage development and maintenance 
+across different TYPO3 versions.
+
+There are two common strategies for managing branches when supporting multiple 
+TYPO3 LTS versions.
+
+.. contents:: Table of Contents:
+   :backlinks: top
+   :class: compact-list
+   :depth: 2
+   :local:
+
+.. _release-branching-strategy-one-branch:
+
+Approach 1: One branch for multiple TYPO3 LTS versions
+======================================================
+
+In this approach, there is a single main branch that receives new features and 
+updates, while supporting multiple TYPO3 LTS versions at the same time.
+
+The downside of this approach is that it may require some version-dependent 
+code switches, which can increase complexity. However, the major advantage is 
+that there is only one branch to maintain, making it easier to implement new 
+features and code changes across all supported TYPO3 versions.
+
+This approach simplifies the maintenance of the extension and is preferred when 
+minimizing maintenance overhead is the primary concern.
+
+.. _release-branching-strategy-multiple-branches:
+
+Approach 2: Separate branch per TYPO3 LTS version
+=================================================
+
+In this approach, there is one main branch for each TYPO3 LTS version. This 
+means that each branch exclusively supports a single TYPO3 LTS version.
+
+The advantage here is that version-specific code can be used without requiring 
+version-dependent switches, reducing complexity in the codebase. However, this 
+approach increases the maintenance burden, as any new features or updates must 
+be applied to each branch individually.
+
+This approach may be necessary when there are significant differences between 
+TYPO3 LTS versions or when you want to avoid version-dependent code.
+
+.. _release-strategy-conclusion:
+
+Conclusion
+==========
+
+The appropriate release and branching strategy depends on the specific 
+requirements of the extension and the TYPO3 versions you are supporting. If 
+reducing maintenance complexity is a priority, using a single branch for 
+multiple versions is often the better choice. However, if you need to tailor 
+your extension for each version, a separate branch for each version may be more 
+suitable.

Documentation/TestingFramework.rst

@@ -1,57 +0,0 @@
-.. include:: /Includes.rst.txt
-
-.. _testing-framework:
-
-=================
-Testing framework
-=================
-
-Extensions usually need to support two LTS versions of TYPO3 in parallel,
-assuming that they should support all currently supported TYPO3 LTS versions.
-To achieve this, there are two different approaches, which also affect the
-choice of a testing framework for unit and functional tests.
-
-.. contents:: Table of Contents:
-   :backlinks: top
-   :class: compact-list
-   :depth: 2
-   :local:
-
-.. _testing-framework-approach-many-versions:
-
-Approach 1: One branch for many TYPO3 LTS versions
-==================================================
-
-With this approach, there is one main branch that gets new features. It needs to
-support two TYPO3 LTS versions in parallel.
-
-The downside is that this slightly increases code complexity as
-version-dependent code switches might be necessary. The upside is that there
-is only one branch to maintain, which makes adding new features (and all other
-code changes) a lot less of a hassle.
-
-The `Nimut testing framework <https://github.com/Nimut/testing-framework>`__
-can support multiple TYPO3 versions at a time, and
-it provides version-independent abstractions for testing, making it the perfect
-companion for this approach.
-
-This is the approach that we have chosen for this extension as we do not want
-to maintain two branches in parallel.
-
-.. _testing-framework-approach-one-version:
-
-Approach 2: One branch per TYPO3 LTS version
-============================================
-
-With this approach, there are two main branches that get new features in
-parallel. Each branch supports exactly one TYPO3 LTS version.
-
-The upside is that this slightly decreases code complexity as
-version-dependent code switches are not necessary. The downside is that there
-are two branches to maintain, which makes adding new features (and all other
-code changes) more of a hassle.
-
-For this approach, the
-`TYPO3 testing framework <https://github.com/TYPO3/testing-framework>`__
-- which supports only one TYPO3 LTS version at a time - will work just fine.
-

composer.json

@@ -54,7 +54,7 @@
 		"php-parallel-lint/php-parallel-lint": "1.4.0",
 		"phpmd/phpmd": "2.15.0",
 		"phpstan/extension-installer": "1.4.3",
-		"phpstan/phpstan": "1.12.5",
+		"phpstan/phpstan": "1.12.6",
 		"phpstan/phpstan-phpunit": "1.4.0",
 		"phpstan/phpstan-strict-rules": "1.6.1",
 		"phpunit/phpunit": "9.6.20",