Support generating alpha releases for GrimoireLab

This updated workflow will generate releases only for grimoirelab-core,
grimoirelab-chronicler, and grimoirelab 2.x alpha versions. Releases
for other packages will not be created until a final release is made.

Signed-off-by: Jose Javier Merchante <jjmerchante@bitergia.com>

Author: jjmerchante

.github/workflows/docker-image.yml

@@ -32,6 +32,8 @@ jobs:
           tags: |
             # Generate a raw tag so latest is not used
             type=raw,value=${{ inputs.version }}
+          build-args: |
+            GRIMOIRELAB_RELEASE=${{ inputs.version }}
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@29109295f81e9208d7d86ff1c6c12d2833863392 # v3.6.0