Orb environment doesn't play nice with CGO

[willscott]

• The orb environment does not include gcc in the images, but also does not set CGO_ENABLED=0.
• https://github.com/libp2p/go-libp2p-quic-transport makes use of github.com/klauspost/compress among other dependencies which default to attempting CGO compilation unless explicitly disabled.
• This leads to failures of the form:

  loadinternal: cannot find runtime/cgo
  /usr/local/go/pkg/tool/linux_amd64/link: running gcc failed: exit status 1
  /bin/ld: cannot find crti.o: No such file or directory
  /bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux-gnu/9/libgcc.a when searching for -lgcc
  /bin/ld: cannot find -lgcc

Do we think we can safely update the orb environment to either include CGO_ENABLED=0 or to provide a parameter for consumers to do so?