separate 24.04 source build from docker build

.github/workflows/ubuntu_22_04_docker.yml

@@ -7,7 +7,6 @@ on:
 jobs:
   ubuntu2204docker:
     runs-on: ubuntu-22.04
-    # env:
     steps:
       - name: git clone [email protected]:lucasw/ros_from_src
         uses: actions/checkout@v2

.github/workflows/ubuntu_24_04.yaml → .github/workflows/ubuntu_24_04.yml

@@ -5,7 +5,7 @@ on:
   workflow_dispatch:
 
 jobs:
-  ubuntu2404dockeron2204:
+  ubuntu2404:
     runs-on: ubuntu-24.04
     # env:
     steps:
@@ -40,11 +40,3 @@ jobs:
         run: |
           cd staging
           underlay_ws/catkin.sh
-
-      - name: docker build from source 24.04
-        run: |
-          cd ros_from_src
-          docker build --build-arg IMAGE=ubuntu:24.04 --build-arg SUBDIR=ubuntu_2404 . -t ros2404
-
-          # TODO(lucasw) ubuntu_2404/Dockerfile doesn't work, was depending on the now-removed
-          # apt debian science ros packages

.github/workflows/ubuntu_24_04_docker.yml

@@ -0,0 +1,23 @@
+name: Ubuntu 24.04 Noetic ROS build from source in docker
+
+on:
+  push:
+  workflow_dispatch:
+
+jobs:
+  ubuntu2404docker:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: git clone [email protected]:lucasw/ros_from_src
+        uses: actions/checkout@v4
+        with:
+          path: ros_from_src
+          submodules: recursive
+
+      - name: docker build from source 24.04
+        run: |
+          cd ros_from_src
+          docker build --build-arg IMAGE=ubuntu:24.04 --build-arg SUBDIR=ubuntu_2404 . -t ros2404
+
+          # TODO(lucasw) ubuntu_2404/Dockerfile doesn't work, was depending on the now-removed
+          # apt debian science ros packages