Special-case go modules in convertedToBazel

This function is called in getOtherModuleLabel, and is used to mark the
otherModule as an unconvertedDep. This meant that if a soong module `A`
depends on soong_zip, it would add soong_zip as unconverted dep of `A`.
All go modules have been converted in bp2build, so this CL special
cases go_package and go_binary in this function.

Bug: 294098662
Test: printf metrics in build_conversion.go# GenerateBazelTargets, and
made sure that the string "has unconverted.*soong_zip" does not appear

Change-Id: I8d1d0876c581f9b2eb72dafcb3a28bd5577bbb4c