GitHub Actions: Update actions/checkout version and stop using Mambaforge

[traversaro]

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[traversaro]

APT CI fails with:

[ 94%] Building CXX object tests/CMakeFiles/ControlBoardControlTest.dir/ControlBoardControlTest.cc.o
[ 95%] Linking CXX executable ../bin/ControlBoardControlTest
/usr/bin/ld: CMakeFiles/ControlBoardControlTest.dir/ControlBoardControlTest.cc.o: undefined reference to symbol '_ZN3tbb6detail2r114notify_waitersEm'
/usr/bin/ld: /lib/x86_64-linux-gnu/libtbb.so.12: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
gmake[2]: *** [tests/CMakeFiles/ControlBoardControlTest.dir/build.make:240: bin/ControlBoardControlTest] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:1794: tests/CMakeFiles/ControlBoardControlTest.dir/all] Error 2
gmake: *** [Makefile:146: all] Error 2

I have no idea how to debug this, I think it is just easier to drop apt CI.