CI: added dispatch_workflow for ros2 jobs

.github/workflows/docker-ros2.yml

@@ -5,6 +5,7 @@ on:
     branches: [ ros2 ]
   pull_request:
     branches: [ ros2 ]
+  workflow_dispatch:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
@@ -12,6 +13,8 @@ concurrency:
 
 jobs:
   docker:
+    # A manual dispatch is honored only on ros2, the only ref we push from.
+    if: ${{ github.event_name != 'workflow_dispatch' || github.ref == 'refs/heads/ros2' }}
     runs-on: ubuntu-latest
     
     strategy:

.github/workflows/ros2.yml

@@ -6,6 +6,7 @@ on:
     branches: [ ros2 ]
   pull_request:
     branches: [ ros2 ]
+  workflow_dispatch:
 
 env:
   BUILD_TYPE: Release