[#6] Allow choosing which image to rebuild manually

Signed-off-by: Vitaliy Potyarkin <v.potyarkin@yadro.com>

.forgejo/workflows/build.yml

@@ -2,6 +2,12 @@ on:
   push:
   pull_request:
   workflow_dispatch:
+    inputs:
+      image:
+        description: Which image to build
+        default: none
+        required: false
+        type: string
 
 jobs:
   build:
@@ -38,7 +44,7 @@ jobs:
         run: make push-${{matrix.tag}}
         if: >-
           github.ref == 'refs/heads/master' &&
-          (github.event_name == 'workflow_dispatch' ||
+          ((github.event_name == 'workflow_dispatch' && github.event.inputs.image == matrix.tag) ||
           (steps.changed.outputs.any_changed == 'true' && github.event_name == 'push'))
         env:
           REGISTRY_PASSWORD: ${{secrets.FORGEJO_OCI_REGISTRY_PUSH_TOKEN}}