.github: Install local pymavlink

Signed-off-by: Ryan Friedman <[email protected]>

.github/workflows/colcon.yml

@@ -171,7 +171,7 @@ jobs:
           cd src
           wget --progress=dot:giga https://raw.githubusercontent.com/ArduPilot/ardupilot/master/Tools/ros2/ros2.repos
           vcs import --recursive --debug --shallow --skip-existing < ros2.repos
-      - name: Install dependencies
+      - name: Install rosdep dependencies
         shell: 'bash'
         run: |
           apt update
@@ -181,9 +181,15 @@ jobs:
           python -m pip install flake8==3.7.9
           source /opt/ros/humble/setup.bash
           rosdep install --from-paths src --ignore-src --default-yes
-          # Install these specific versions just to prevent rolling updates.
+      - name: Install MAVProxy
+        run: |
+          # Install this specific version just to prevent rolling updates.
           # These are the latest available
-          python3 -m pip install MAVProxy==1.8.67 pymavlink==2.4.40
+          python3 -m pip install MAVProxy==1.8.67
+      - name: Install local pymavlink
+        working-directory: ./src/ardupilot/modules/mavlink/pymavlink
+        run: |
+          pip install . -U --user
       - name: Build with colcon
         shell: 'bash'
         run: |