Remove Zen 4 nightly build from unsupported compiler versions

[ripatel-fd]

The following nightly checks don't work
https://github.com/firedancer-io/firedancer/actions/workflows/builds.yml

  source /opt/gcc/gcc-10.5.0/activate
  ./deps.sh nuke
  FD_AUTO_INSTALL_PACKAGES=1 ./deps.sh +dev fetch check install
  make -j distclean
  MACHINE=linux_gcc_zen4 CC=gcc make -j all asm ppp unit-test fuzz-test fdctl fddev integration-test

  source /opt/gcc/gcc-11.4.0/activate
  ./deps.sh nuke
  FD_AUTO_INSTALL_PACKAGES=1 ./deps.sh +dev fetch check install
  make -j distclean
  MACHINE=linux_gcc_zen4 CC=gcc make -j all asm ppp unit-test fuzz-test fdctl fddev integration-test

Results in cc1: error: bad value (‘znver4’) for ‘-mtune=’ switch because GCC 10 and 11 don't recognize znver4.