Fix Qt5-Qt6 co-install #52

Job	Run time
build (ubuntu-22.04, Debug, static, 5.15)	4m 15s
build (ubuntu-22.04, Debug, static, 6.5.*)	5m 15s
build (ubuntu-22.04, Debug, shared, 5.15)	4m 11s
build (ubuntu-22.04, Debug, shared, 6.5.*)	6m 26s
build (ubuntu-22.04, Release, static, 5.15)	1m 3s
build (ubuntu-22.04, Release, static, 6.5.*)	1m 29s
build (ubuntu-22.04, Release, shared, 5.15)	1m 12s
build (ubuntu-22.04, Release, shared, 6.5.*)	1m 22s
build (windows-2022, Debug, static, 5.15)	15m 41s
build (windows-2022, Debug, static, 6.5.*)	17m 36s
build (windows-2022, Debug, shared, 5.15)	16m 15s
build (windows-2022, Debug, shared, 6.5.*)	17m 34s
build (windows-2022, Release, static, 5.15)	1m 50s
build (windows-2022, Release, static, 6.5.*)	2m 44s
build (windows-2022, Release, shared, 5.15)	3m 24s
build (windows-2022, Release, shared, 6.5.*)	3m 30s
build (macos-12, Debug, static, 5.15)	8m 5s
build (macos-12, Debug, static, 6.5.*)	10m 26s
build (macos-12, Debug, shared, 5.15)	6m 52s
build (macos-12, Debug, shared, 6.5.*)	10m 35s
build (macos-12, Release, static, 5.15)	1m 21s
build (macos-12, Release, static, 6.5.*)	2m 0s
build (macos-12, Release, shared, 5.15)	1m 26s
build (macos-12, Release, shared, 6.5.*)	3m 28s
	2h 28m 0s

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