build: update branch reference in markdown-autodocs usage for consistency

Author: roboticswithjulia

.github/workflows/rust-minimal.yml

@@ -39,7 +39,7 @@ jobs:
       uses: dineshsonachalam/[email protected]
       with:
         commit_message: Synchronizing Markdown files
-        branch: ${{ github.head_ref }} 
+        branch: ${{ github.base_ref }} 
         output_file_paths: '[./docs/writing-your-first-rclrs-node.md]'
         categories: '[code-block]'
 
@@ -81,7 +81,6 @@ jobs:
       id: build
       uses: ros-tooling/[email protected]
       with:
-        branch: ${{ github.base_ref }} 
         package-name: ${{ steps.list_packages.outputs.package_list }}
         target-ros2-distro: ${{ matrix.ros_distribution }}
         vcs-repo-file-url: ros2_rust_${{ matrix.ros_distribution }}.repos

.github/workflows/rust-stable.yml

@@ -39,7 +39,7 @@ jobs:
       uses: dineshsonachalam/[email protected]
       with:
         commit_message: Synchronizing Markdown files
-        branch: ${{ github.head_ref }} 
+        branch: ${{ github.base_ref }} 
         output_file_paths: '[./docs/writing-your-first-rclrs-node.md]'
         categories: '[code-block]'
 
@@ -81,7 +81,6 @@ jobs:
       id: build
       uses: ros-tooling/[email protected]
       with:
-        branch: ${{ github.base_ref }} 
         package-name: ${{ steps.list_packages.outputs.package_list }}
         target-ros2-distro: ${{ matrix.ros_distribution }}
         vcs-repo-file-url: ros2_rust_${{ matrix.ros_distribution }}.repos