TBR: ref: Remove .v23 from all .gitignore files.
TBR: ref: Remove .v23 from all .gitignore files.

MultiPart: 7/25

Change-Id: I00812bd02e05a658445b62956a7f0268b1fc9e83

vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref