Updated GitHub workflow for releases

no issue

- removed unused environment variables
- hardcoded Node v10 as this is what 2.x supports
- removed extra git line that is now a feature of the checkout Action

.github/workflows/release.yml

@@ -8,9 +8,6 @@ jobs:
     runs-on: ubuntu-latest
     env:
       RELEASE_TOKEN: ${{ secrets.RELEASE_TOKEN }}
-      SENTRY_AUTH_TOKEN: ${{ secrets.SENTRY_AUTH_TOKEN }}
-      SENTRY_ORG: ghost-foundation
-      SENTRY_PROJECT: ghost
       NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
       FORCE_COLOR: 1
     steps:
@@ -18,7 +15,9 @@ jobs:
         with:
           fetch-depth: 0
           submodules: true
-      - run: git fetch --depth=1 origin +refs/tags/*:refs/tags/*
+      - uses: actions/setup-node@v1
+        with:
+          node-version: '10'
       - run: yarn
 
       - run: grunt release:2.x --skip-tests