Don't run 'make_release' on pull requests (#278)

This step is only relevant to the 'push' CI workflow.

.github/workflows/ci.yml

@@ -149,40 +149,3 @@ jobs:
 
     - name: workspace_v2
       run: make workspace_v2
-
-  # This uploads `xchammer.zip` as an artifact to github actions
-  # For issues mentioned here
-  # https://github.com/actions/upload-artifact/issues/50
-  # The Github URL can't be used with Bazel directly in an `http_archive`
-  # At the time of writing the only way to consume it is to:
-  # - get the release URL with the github actions API which is valid for 1 minute
-  # - pull the zip from that URL and re-host it: or somehow use it locally.
-  # - it'd probably be possible to impalement as a github actions repository
-  #   and that's a lot of unwarranted complexity to integrate XCHammer.
-  #
-  # See README.md of how to use the artifact with Bazel
-  make_release:
-    name: make_release
-    runs-on: macOS-latest
-    steps:
-      - uses: actions/checkout@v2
-      - name: bazel_cache_release
-        uses: actions/cache@v2
-        env:
-          cache-name: bazel-cache-release
-        with:
-          path: ~/Library/Caches/Bazel
-          key: ${{ runner.os }}-build-${{ env.cache-name }}
-          restore-keys: ${{ runner.os }}-build-${{ env.cache-name }}-
-
-      - name: make_release
-        run: |
-            make release
-            # Set the BAZEL_BIN env var to the realpath
-            # Note: actions/upload-artifact@v2 at time of writing is falling
-            # apart when we give it a symlink base path
-            echo ::set-env name=BAZEL_BIN::$(readlink bazel-bin)
-      - uses: actions/upload-artifact@v2
-        with:	
-          name: xchammer
-          path: ${{ env.BAZEL_BIN }}/xchammer_dist_repo.zip