Do not use a shell in `proc_open()` if not really needed #922

Job	Run time
Dependency Validation	9s
Coding Guidelines	44s
Type Checker	26s
Unit Tests (ubuntu-latest, 8.1)	11s
Unit Tests (ubuntu-latest, 8.2)	11s
Unit Tests (ubuntu-latest, 8.3)	11s
Unit Tests (ubuntu-latest, 8.4)	13s
Unit Tests (windows-latest, 8.1)	32s
Unit Tests (windows-latest, 8.2)	32s
Unit Tests (windows-latest, 8.3)	31s
Unit Tests (windows-latest, 8.4)	28s
End-to-End Tests (ubuntu-latest, 8.1)	14s
End-to-End Tests (ubuntu-latest, 8.2)	15s
End-to-End Tests (ubuntu-latest, 8.3)	11s
End-to-End Tests (ubuntu-latest, 8.4)	10s
End-to-End Tests (windows-latest, 8.1)	36s
End-to-End Tests (windows-latest, 8.2)	38s
End-to-End Tests (windows-latest, 8.3)	29s
End-to-End Tests (windows-latest, 8.4)	29s
Build PHAR	0s
Code Coverage	0s
Test PHAR	0s
	7m 10s

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