Allow rolling job to fail. Force install of known to work version of (#…

…302)

pydocstyle. Schedule CI runs every night.

.github/workflows/rust.yml

@@ -5,6 +5,8 @@ on:
     branches: [ main ]
   pull_request:
     branches: [ main ]
+  schedule:
+    - cron: '0 0 * * *'
 
 env:
   CARGO_TERM_COLOR: always
@@ -36,6 +38,7 @@ jobs:
             ros_distribution: rolling
             ros_version: 2
     runs-on: ubuntu-latest
+    continue-on-error: ${{ matrix.ros_distribution == 'rolling' }}
     container:
       image: ${{ matrix.docker_image }}
     steps:
@@ -51,6 +54,10 @@ jobs:
       with:
         required-ros-distributions: ${{ matrix.ros_distribution }}
 
+    - name: Downgrade pydocstyle as a workaround for https://github.com/ament/ament_lint/issues/434
+      run: |
+        sudo pip install pydocstyle==6.1.1
+
     - name: Setup Rust
       uses: dtolnay/rust-toolchain@1.63.0
       with: