Update GitHub Actions workflows.

.github/workflows/build_sdk.yml

@@ -35,7 +35,9 @@ jobs:
     name: build_sdk
     runs-on: ubuntu-latest
     strategy:
-      fail-fast: true
+      # We normally fail fast unless this is a PR from Renovate in which case
+      # we'll always build all SDKs in case there are any changes to commit.
+      fail-fast: ${{ ! contains(github.actor, 'renovate') }}
       matrix:
         language:
         - nodejs
@@ -69,14 +71,52 @@ jobs:
       - name: Build SDK
         run: make build_${{ matrix.language }}
       - name: Check worktree clean
+        id: worktreeClean
         uses: pulumi/git-status-check-action@v1
         with:
+          # Keep these in sync with the Renovate step below to avoid them getting checked in.
           allowed-changes: |
             sdk/**/pulumi-plugin.json
             sdk/dotnet/*.csproj
             sdk/go/**/pulumiUtilities.go
             sdk/nodejs/package.json
             sdk/python/pyproject.toml
+      - name: Commit ${{ matrix.language }} SDK changes for Renovate
+        # If the worktree is dirty and this is a Renovate PR to bump
+        # dependencies, commit the updated SDK and push it back to the PR. The
+        # job will still be marked as a failure.
+        if: failure() && steps.worktreeClean.outcome == 'failure' && contains(github.actor, 'renovate')
+        shell: bash
+        run: |
+          git config --global user.email "[email protected]"
+          git config --global user.name "pulumi-bot"
+
+          # Stash local changes and check out the PR's branch directly.
+          git stash
+          git fetch
+          git checkout "origin/$HEAD_REF"
+
+          # Apply and add our changes, but don't commit any files we expect to
+          # always change due to versioning.
+          git stash pop
+          git add sdk
+          git reset \
+              sdk/python/*/pulumi-plugin.json \
+              sdk/dotnet/Pulumi.*.csproj \
+              sdk/go/*/internal/pulumiUtilities.go \
+              sdk/nodejs/package.json \
+              sdk/python/pyproject.toml
+          git commit -m 'Commit ${{ matrix.language }} SDK for Renovate'
+
+          # Push with pulumi-bot credentials to trigger a re-run of the
+          # workflow. https://github.com/orgs/community/discussions/25702
+          git push https://pulumi-bot:${{ secrets.PULUMI_BOT_TOKEN }}@github.com/${{ github.repository }} \
+              "HEAD:$HEAD_REF"
+        env:
+          # head_ref is untrusted so it's recommended to pass via env var to
+          # avoid injections.
+          HEAD_REF: ${{ github.head_ref }}
+
       - name: Upload SDK
         uses: ./.github/actions/upload-sdk
         with: