Remove unused Maven call

Author: atextor

.github/workflows/release-workflow.yml

@@ -29,7 +29,6 @@ jobs:
       - name: Sanity check version
         if: ${{ !contains( github.event.inputs.release_version, '-M' ) }}
         run: |
-          current_version=$(mvn help:evaluate -Dexpression=project.version -q -DforceStdout)
           release_version=${{ github.event.inputs.release_version }}
 
           if [[ $release_version =~ ^[0-9]+.[0-9]+.[0-9]+$ ]]