fix(ci): add repo guard to prevent CI running on mirrors

All three jobs now have if: github.repository == 'Interested-Deving-1896/liqxanmod'.
This stops the build triggering on OSP and OOC mirror pushes, which were
failing on every sync. Matches the pattern used in xanmod-unified-kernel
and liquorix-unified-kernel.

Author: Interested-Deving-1896

.github/workflows/build.yml

@@ -24,6 +24,7 @@ jobs:
   shellcheck:
     name: Shellcheck
     runs-on: ubuntu-latest
+    if: github.repository == 'Interested-Deving-1896/liqxanmod'
     steps:
       - uses: actions/checkout@v4
       - name: Install shellcheck
@@ -37,6 +38,7 @@ jobs:
     name: Build (${{ matrix.distro }} / ${{ matrix.mode }})
     runs-on: ubuntu-latest
     needs: shellcheck
+    if: github.repository == 'Interested-Deving-1896/liqxanmod'
     strategy:
       fail-fast: false
       matrix:
@@ -157,7 +159,7 @@ jobs:
     name: Release
     runs-on: ubuntu-latest
     needs: build-matrix
-    if: github.ref == 'refs/heads/main' && github.event_name == 'push'
+    if: github.repository == 'Interested-Deving-1896/liqxanmod' && github.ref == 'refs/heads/main' && github.event_name == 'push'
     permissions:
       contents: write
       id-token: write