Fix PHPStan failures #694

Job	Run time
Coding Standard	19s
Lint (7.4)	14s
PHPStan (7.4)	15s
Lint (8.0)	25s
PHPStan (8.0)	23s
Lint (8.1)	11s
Tests (ubuntu-latest, 7.4, lowest)	12s
PHPStan (8.1)	20s
Lint (8.2)	15s
Tests (ubuntu-latest, 7.4, highest)	15s
PHPStan (8.2)	17s
Tests (ubuntu-latest, 8.0, lowest)	12s
Lint (8.3)	11s
PHPStan (8.3)	15s
Tests (ubuntu-latest, 8.0, highest)	12s
Lint (8.4)	10s
PHPStan (8.4)	21s
Tests (ubuntu-latest, 8.1, lowest)	17s
Tests (ubuntu-latest, 8.1, highest)	14s
Tests (ubuntu-latest, 8.2, lowest)	14s
Tests (ubuntu-latest, 8.2, highest)	19s
Tests (ubuntu-latest, 8.3, lowest)	15s
Tests (ubuntu-latest, 8.3, highest)	13s
Tests (ubuntu-latest, 8.4, lowest)	14s
Tests (ubuntu-latest, 8.4, highest)	11s
Tests (windows-latest, 7.4, lowest)	32s
Tests (windows-latest, 7.4, highest)	31s
Tests (windows-latest, 8.0, lowest)	29s
Tests (windows-latest, 8.0, highest)	35s
Tests (windows-latest, 8.1, lowest)	30s
Tests (windows-latest, 8.1, highest)	29s
Tests (windows-latest, 8.2, lowest)	33s
Tests (windows-latest, 8.2, highest)	37s
Tests (windows-latest, 8.3, lowest)	27s
Tests (windows-latest, 8.3, highest)	28s
Tests (windows-latest, 8.4, lowest)	31s
Tests (windows-latest, 8.4, highest)	28s
	12m 34s

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