Fixes for missing rules in m --soong-only

This CL
1. Disables filesystem diff test if there is no kati invocation, since
   there will not be a file_list.txt to do the comparison
2. Disables installation for goBinary if it is in an unexported
   namespace.

Test: m checkbuild --soong-build (top of stack)
Bug: 394096939
Change-Id: I5057c2cc431f5e8db12816c3dacf69b3159e18d5