fix: fix ref for docker image build (#14)

Signed-off-by: Jacques Samain <jsamain@cisco.com>

Author: Castorche

.github/workflows/api_docker_image_release.yaml

@@ -32,7 +32,7 @@ jobs:
           # This assumes tags are in this form
           # api-v<version>
 
-          _target=api
+          _target=${GITHUB_REF_NAME}
           target=${_target%-v*}
 
           # get version only

.github/workflows/mce_docker_image_release.yaml

@@ -32,7 +32,7 @@ jobs:
           # This assumes tags are in this form
           # mce-v<version>
 
-          _target=mce
+          _target=${GITHUB_REF_NAME}
           target=${_target%-v*}
 
           # get version only