Fix CI external repo getters (#498)

Signed-off-by: Jesus Perez <[email protected]>

Author: jepemi

.github/workflows/reusable-ubuntu-ci.yml

@@ -129,27 +129,31 @@ jobs:
         with:
           remote_repository: eProsima/Fast-DDS
           fallback_branch: ${{ inputs.fastdds-branch }}
+          skip_base: true
 
       - name: Get Fast CDR branch
         id: get_fastcdr_branch
         uses: eProsima/eProsima-CI/ubuntu/get_related_branch_from_repo@v0
         with:
           remote_repository: eProsima/Fast-CDR
           fallback_branch: ${{ inputs.fastcdr-branch }}
+          skip_base: true
 
       - name: Get Fast DDS Python branch
         id: get_fastdds_python_branch
         uses: eProsima/eProsima-CI/ubuntu/get_related_branch_from_repo@v0
         with:
           remote_repository: eProsima/Fast-DDS-python
-          fallback_branch: main
+          fallback_branch: ${{ inputs.fastdds-python-branch }}
+          skip_base: true
 
       - name: Get Discovery Server branch
         id: get_discovery_server_branch
         uses: eProsima/eProsima-CI/ubuntu/get_related_branch_from_repo@v0
         with:
           remote_repository: eProsima/Discovery-Server
-          fallback_branch: master
+          fallback_branch: ${{ inputs.discovery-server-branch }}
+          skip_base: true
 
       - name: Download Fast CDR, Fast DDS Python, and Discovery Server
         run: |