chore: wip manual-release workflow

.github/workflows/manual-release.yml

@@ -0,0 +1,45 @@
+# This workflow is used on the rare occassion we need to manually cut a release.
+# It can be triggered via the Github UI or the Github API.
+
+name: Manual publish to Github Releases and NPM
+
+on:
+  workflow_dispatch:
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        # We need to fetch all tags and branches
+        fetch-depth: 0
+
+    - name: Verify head of master hasn't changed
+      run: |
+        # We ensure that the latest commit on master is still the one we expected when
+        # we started the release job, otherwise we exit
+        if [ "$GITHUB_SHA" != "$(git rev-parse --verify HEAD)" ]; then
+            echo "ERROR: The commit SHA at the HEAD of master has changed"
+            echo "Expected: $GITHUB_SHA"
+            echo "Actual: $(git rev-parse --verify HEAD)"
+            exit 1;
+        fi
+
+    - name: Get yarn cache directory path
+      id: yarn-cache-dir-path
+      run: echo "::set-output name=dir::$(yarn cache dir)"
+
+    - uses: actions/cache@v2
+      id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
+      with:
+        path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
+        key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-yarn-
+
+    - name: Install dependencies
+      run: yarn --frozen-lockfile
+
+    - name: (WIP) Determine what version to release
+      run: npx lerna version --loglevel=silly --conventional-commits --exact