rolling is now the default branch, update CI and README accordingly

Signed-off-by: Mikael Arguedas <[email protected]>

.github/workflows/test.yml

@@ -28,7 +28,7 @@ jobs:
         target-ros2-distro: rolling
     - name: Upload coverage to Codecov
       uses: codecov/codecov-action@v1
-      if: github.event_name == 'pull_request' || (github.event_name == 'push' && github.ref == 'refs/heads/master')
+      if: github.event_name == 'pull_request' || (github.event_name == 'push' && github.ref == 'refs/heads/rolling')
       with:
         file: ros_ws/build/sros2/coverage.xml
         flags: unittests

README.md

@@ -1,7 +1,7 @@
 # Context
 
-[![SROS2 CI](https://github.com/ros2/sros2/workflows/SROS2%20CI/badge.svg)](https://github.com/ros2/sros2/actions?query=workflow%3A%22SROS2+CI%22+branch%3Amaster)
-[![codecov](https://codecov.io/gh/ros2/sros2/branch/master/graph/badge.svg)](https://codecov.io/gh/ros2/sros2)
+[![SROS2 CI](https://github.com/ros2/sros2/workflows/SROS2%20CI/badge.svg)](https://github.com/ros2/sros2/actions?query=workflow%3A%22SROS2+CI%22+branch%3Arolling)
+[![codecov](https://codecov.io/gh/ros2/sros2/branch/rolling/graph/badge.svg)](https://codecov.io/gh/ros2/sros2)
 
 This package provides the tools and instructions to use ROS 2 on top of DDS-Security.
 The security feature is tested across platforms (Linux, macOS, and Windows) as well as across different languages (C++ and Python).