replace Qt_VERSION_MAJOR with the more standard QT_VERSION_MAJOR #60

Job	Run time
build (ubuntu-22.04, Debug, static, 5.15)	3m 32s
build (ubuntu-22.04, Debug, static, 6.5.*)	6m 6s
build (ubuntu-22.04, Debug, shared, 5.15)	4m 2s
build (ubuntu-22.04, Debug, shared, 6.5.*)	5m 18s
build (ubuntu-22.04, Release, static, 5.15)	1m 36s
build (ubuntu-22.04, Release, static, 6.5.*)	1m 25s
build (ubuntu-22.04, Release, shared, 5.15)	1m 5s
build (ubuntu-22.04, Release, shared, 6.5.*)	1m 21s
build (windows-2022, Debug, static, 5.15)	14m 32s
build (windows-2022, Debug, static, 6.5.*)	16m 37s
build (windows-2022, Debug, shared, 5.15)	14m 32s
build (windows-2022, Debug, shared, 6.5.*)	16m 36s
build (windows-2022, Release, static, 5.15)	1m 33s
build (windows-2022, Release, static, 6.5.*)	2m 41s
build (windows-2022, Release, shared, 5.15)	2m 4s
build (windows-2022, Release, shared, 6.5.*)	2m 7s
build (macos-12, Debug, static, 5.15)	2m 51s
build (macos-12, Debug, static, 6.5.*)	7m 0s
build (macos-12, Debug, shared, 5.15)	2m 48s
build (macos-12, Debug, shared, 6.5.*)	7m 18s
build (macos-12, Release, static, 5.15)	1m 37s
build (macos-12, Release, static, 6.5.*)	2m 24s
build (macos-12, Release, shared, 5.15)	2m 10s
build (macos-12, Release, shared, 6.5.*)	3m 17s
	2h 4m 32s

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