Don't attest from forks

Author: maresb

.github/workflows/pypi.yml

@@ -37,6 +37,8 @@ jobs:
 
       - name: Attest GitHub build provenance
         uses: actions/attest-build-provenance@v2
+        # Don't attest from forks
+        if: github.repository_owner == 'pymc-devs'
         with:
           subject-path: dist/*.tar.gz
 
@@ -82,6 +84,8 @@ jobs:
 
       - name: Attest GitHub build provenance
         uses: actions/attest-build-provenance@v2
+        # Don't attest from forks
+        if: github.repository_owner == 'pymc-devs'
         with:
           subject-path: ./wheelhouse/*.whl
 
@@ -117,6 +121,8 @@ jobs:
 
       - name: Attest GitHub build provenance
         uses: actions/attest-build-provenance@v2
+        # Don't attest from forks
+        if: github.repository_owner == 'pymc-devs'
         with:
           subject-path: dist/*.whl