Change branching strategy (#142)

* Change branching strategy - now `master` targets Foxy and `dashing-eloquent` targets Dashing and Eloquent

fix https://github.com/ros2/rmw_cyclonedds/issues/128

.github/workflows/CI.yml

@@ -5,15 +5,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-          rosdistro: [dashing, eloquent, master]
+          rosdistro: [master]
           os: [ubuntu-18.04, macOS-latest, windows-latest]
-          exclude:
-            # pending https://github.com/ament/ament_cmake/pull/233
-            - rosdistro: eloquent
-              os: windows-latest
-            # pending https://github.com/ament/ament_cmake/pull/234
-            - rosdistro: dashing
-              os: windows-latest
     runs-on: ${{ matrix.os }}
     steps:
     - if: runner.os == 'Linux'