Use venv for python dependencies in CI #702

Job	Run time
build (ubuntu-24.04, x64-linux, gcc, ubuntu-24.04, Unix Makefiles)	41s
build (ubuntu-22.04, x64-linux, gcc, ubuntu-22.04, Unix Makefiles)	33s
build (ubuntu-20.04, x64-linux, gcc, ubuntu-20.04, Unix Makefiles)	23s
build (macOS, arm64-osx, clang, macOS-latest, Unix Makefiles, /usr/local/share/vcpkg, /Users/runn...	50s
build (windows-x64-vs, x64-windows, vs, x64, windows-latest, Ninja, C:/vcpkg, C:/Users/runneradmi...	8m 10s
build (windows-x86-vs, x86-windows, vs, x86, windows-latest, Ninja, C:/vcpkg, C:/Users/runneradmi...	8m 23s
build (windows-x64-static-vs, x64-windows-static, vs, x64, windows-latest, Ninja, C:/vcpkg, C:/Us...	7m 39s
build (windows-x64-mingw, x64-windows, mingw, windows-latest, Ninja, C:/vcpkg, C:/Users/runneradm...	9m 22s
	36m 1s

Provide feedback