use tip of PR

.github/workflows/ci.yml

@@ -472,11 +472,6 @@ jobs:
           pattern: coverage-*
           merge-multiple: true
           path: coverage
-      - name: Set codecov PR base
-        run: |
-          curl -Os https://cli.codecov.io/latest/linux/codecov
-          sudo chmod +x codecov
-          ./codecov pr-base-picking --base-sha "$(git ls-remote https://github.com/pulumi/pulumi refs/heads/master | cut -f 1)" --pr ${{ github.event.number }} --slug pulumi/pulumi --token ${{ secrets.CODECOV_TOKEN }} --service github
       - name: Upload code coverage
         uses: codecov/codecov-action@v4
         with:
@@ -485,8 +480,6 @@ jobs:
           fail_ci_if_error: false
           verbose: true
           token: ${{ secrets.CODECOV_TOKEN }}
-          override_commit: ${{ github.sha }}
-          override_pr: ${{ github.event.number }}
   build-release-binaries:
     # This overwrites the previously built testing binaries with versions without coverage.
     name: Rebuild binaries

.github/workflows/on-pr.yml

@@ -28,7 +28,7 @@ jobs:
     permissions:
       contents: read
     with:
-      ref: ${{ github.ref }}
+      ref: ${{ github.head_ref }}
       is-snapshot: true
     secrets: inherit
 

codecov.yml

@@ -4,7 +4,6 @@ coverage:
     # Project tracks and reports the project-level coverage.
     project:
       default:
-        base: latest
         informational: true
 
       # Pulumi core