fix extension initialization (fixes #123, via #126) #142

Job	Run time
PHP 8.0 on ubuntu-latest ()	24s
PHP 8.0 on ubuntu-latest (--prefer-lowest)	19s
PHP 8.0 on windows-latest ()	1m 11s
PHP 8.0 on windows-latest (--prefer-lowest)	1m 10s
PHP 8.0 on macOS-latest ()	1m 17s
PHP 8.0 on macOS-latest (--prefer-lowest)	1m 22s
PHP 8.1 on ubuntu-latest ()	26s
PHP 8.1 on ubuntu-latest (--prefer-lowest)	31s
PHP 8.1 on windows-latest ()	1m 39s
PHP 8.1 on windows-latest (--prefer-lowest)	2m 50s
PHP 8.1 on macOS-latest ()	1m 23s
PHP 8.1 on macOS-latest (--prefer-lowest)	1m 19s
PHP 8.2 on ubuntu-latest ()	20s
PHP 8.2 on ubuntu-latest (--prefer-lowest)	19s
PHP 8.2 on windows-latest ()	1m 7s
PHP 8.2 on windows-latest (--prefer-lowest)	1m 19s
PHP 8.2 on macOS-latest ()	1m 36s
PHP 8.2 on macOS-latest (--prefer-lowest)	2m 29s
PHP 8.3 on ubuntu-latest ()	20s
PHP 8.3 on ubuntu-latest (--prefer-lowest)	31s
PHP 8.3 on windows-latest ()	57s
PHP 8.3 on windows-latest (--prefer-lowest)	1m 3s
PHP 8.3 on macOS-latest ()	1m 21s
PHP 8.3 on macOS-latest (--prefer-lowest)	2m 10s
	27m 23s

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