move MM notification to a separate job step so it's in its own contai…

…ner (#1029)

* move MM notification to a separate job step

Change-Id: I1c30760aa4886d16a18ba64aa10e0ca5cb7b7576
Signed-off-by: nickboldt <nboldt@redhat.com>

* Florent prefers ubuntu-20.04 to ubuntu-latest as it's more stable (but also introduces future maintenance)

Change-Id: Iec9e3f22f7865c446c5979a65c440f5484416b8e
Signed-off-by: nickboldt <nboldt@redhat.com>

* Update release.yml

job 'notify' needs job 'build'

.github/workflows/release.yml

@@ -83,6 +83,10 @@ jobs:
     - name: Publish packages to npmjs
       if: github.event.inputs.pushToNpmJs == true 
       run: yarn publish:next
+  notify:
+    runs-on: ubuntu-20.04
+    needs: build
+    steps:
     - name: Create MM message
       run: |
         echo "{\"text\":\":building_construction: Che Theia ${{ github.event.inputs.version }} has been released: https://quay.io/eclipse/che-theia-dev:${{ github.event.inputs.version }} https://quay.io/eclipse/che-theia:${{ github.event.inputs.version }} https://quay.io/eclipse/che-theia-endpoint-runtime-binary:${{ github.event.inputs.version }}\"}" > mattermost.json