ci: remove ABI input from gap-actions/build-pkg

Author: james-d-mitchell

.github/workflows/extended.yml

@@ -74,7 +74,6 @@ jobs:
         uses: gap-actions/build-pkg@v3
         with:
           CONFIGFLAGS: --disable-hpcombi
-          ABI: ${{ matrix.ABI }}
         env:
           ABI: ${{ matrix.ABI }}
       - name: "Run GAP's tst/teststandard.g"