git: Fix repo url and hash that gets sent to the ImHex-Patterns repo

Author: WerWolv

.github/workflows/tests.yml

@@ -88,5 +88,13 @@ jobs:
     needs: tests
     uses: WerWolv/ImHex-Patterns/.github/workflows/tests.yml@master
     with:
-      pattern_language_git_repo: ${{ github.server_url }}/${{ github.repository }}
-      pattern_language_git_hash: ${{ github.sha }}
+      pattern_language_git_repo: ${{ github.server_url }}/${{
+        github.event_name == 'pull_request'
+        && github.event.pull_request.head.repo.full_name
+        || github.repository
+      }}
+      pattern_language_git_hash: ${{
+        github.event_name == 'pull_request'
+        && github.event.pull_request.head.sha
+        || github.sha
+      }}