Change workflow triggers

Signed-off-by: Nicolas Bock <nicolas.bock@canonical.com>

.github/workflows/docker-publish.yaml

@@ -5,6 +5,9 @@ on:
     workflows: [Test and Build]
     types:
       - completed
+  release:
+    types:
+      - published
 
 env:
   REGISTRY: docker.io
@@ -27,12 +30,6 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Install cosign
-        if: github.event_name != 'pull_request'
-        uses: sigstore/cosign-installer@v3
-        with:
-          cosign-release: 'v2.1.1'
-
       - name: Get packages
         uses: actions/download-artifact@v4
         with:

.github/workflows/ghcr-publish.yaml

@@ -7,6 +7,9 @@ on:
     workflows: [Test and Build]
     types:
       - completed
+  release:
+    types:
+      - published
 
 env:
   REGISTRY: ghcr.io

.github/workflows/test-and-build.yaml

@@ -6,9 +6,6 @@ on:
   push:
     branches:
       - main
-    tags:
-      - 'v*.*.*' # v0.1.2
-      - 'v20*'  # v20240613[-1]
   pull_request:
     branches:
       - main