Docker: Adjust image builder configuration

- Use semver tagging for releases.
- Build images on pull requests.

Author: amotl

.github/workflows/release-docker-full.yml

@@ -44,7 +44,9 @@ jobs:
           # Generate Docker tags based on the following events/attributes
           tags: |
             type=schedule,pattern=nightly
-            type=ref,event=tag
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
       -
         name: Inspect meta
         run: |

.github/workflows/release-docker-standard.yml

@@ -44,7 +44,9 @@ jobs:
           # Generate Docker tags based on the following events/attributes
           tags: |
             type=schedule,pattern=nightly
-            type=ref,event=tag
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
       -
         name: Inspect meta
         run: |