CI: simplify PHP 8.4 config (#212) #501

Job	Run time
checks	30s
tests (7.2, prefer-lowest, ubuntu-latest)	12s
tests (7.2, prefer-lowest, windows-latest)	33s
tests (7.2, prefer-stable, ubuntu-latest)	15s
tests (7.2, prefer-stable, windows-latest)	36s
tests (7.3, prefer-lowest, ubuntu-latest)	15s
tests (7.3, prefer-lowest, windows-latest)	32s
tests (7.3, prefer-stable, ubuntu-latest)	10s
tests (7.3, prefer-stable, windows-latest)	33s
tests (7.4, prefer-lowest, ubuntu-latest)	11s
tests (7.4, prefer-lowest, windows-latest)	33s
tests (7.4, prefer-stable, ubuntu-latest)	10s
tests (7.4, prefer-stable, windows-latest)	34s
tests (8.0, prefer-lowest, ubuntu-latest)	15s
tests (8.0, prefer-lowest, windows-latest)	30s
tests (8.0, prefer-stable, ubuntu-latest)	15s
tests (8.0, prefer-stable, windows-latest)	31s
tests (8.1, prefer-lowest, ubuntu-latest)	11s
tests (8.1, prefer-lowest, windows-latest)	30s
tests (8.1, prefer-stable, ubuntu-latest)	10s
tests (8.1, prefer-stable, windows-latest)	42s
tests (8.2, prefer-lowest, ubuntu-latest)	10s
tests (8.2, prefer-lowest, windows-latest)	34s
tests (8.2, prefer-stable, ubuntu-latest)	14s
tests (8.2, prefer-stable, windows-latest)	35s
tests (8.3, prefer-lowest, ubuntu-latest)	10s
tests (8.3, prefer-lowest, windows-latest)	30s
tests (8.3, prefer-stable, ubuntu-latest)	14s
tests (8.3, prefer-stable, windows-latest)	31s
tests (8.4, prefer-lowest, ubuntu-latest)	15s
tests (8.4, prefer-lowest, windows-latest)	37s
tests (8.4, prefer-stable, ubuntu-latest)	15s
tests (8.4, prefer-stable, windows-latest)	36s
	12m 49s

Provide feedback