The PHPUnit configuration option `controlGarbageCollector` was
introduced for PHPUnit 10 and 11 only and hence is not available
for version 9 yet (the version we're using). So we cannot use
this configuration option yet.
This reverts commit 7dea2ddc0b.
This is disabled by default and enabled with this change.
This has the following effect:
- Deactivate automatic garbage collection using gc_disable() before the
first test is run
- Trigger garbage collection using gc_collect_cycles() before the first
test is run
- Trigger garbage collection using gc_collect_cycles() after each n-th
test
- Trigger garbage collection after using gc_collect_cycles() after the
last test was run
- Activate automatic garbage collection using gc_enable() after the last
test was run
Resolves: #1328
