Use snapshot image for image scan (#4393)

Author: carlesarnal

.github/workflows/image-scan.yaml

@@ -2,23 +2,11 @@ name: Trivy Image Scan
 
 on:
   workflow_dispatch:
-    inputs:
-      image:
-        description: 'Image to be scanned'
-        default: 'quay.io/apicurio/apicurio-registry:latest-snapshot'
-        required: true
   schedule:
     - cron: "0 6 * * *"
 
 jobs:
-  call-image-scan-registry-default:
-    if: ${{ github.event.inputs.image }} == ''
-    uses: Apicurio/apicurio-gh-workflows/.github/workflows/image-scan.yaml@main
-    with:
-      image: quay.io/apicurio/apicurio-registry:latest-snapshot
-
   call-image-scan-registry:
-    if: ${{ github.event.inputs.image }} != ''
     uses: Apicurio/apicurio-gh-workflows/.github/workflows/image-scan.yaml@main
     with:
-      image: ${{ github.event.inputs.image }}
+      image: quay.io/apicurio/apicurio-registry:latest-snapshot