Disable trivy cache

Author: puehringer

.github/workflows/build-docker-artifacts.yml

@@ -295,6 +295,8 @@ jobs:
           ignore-unfixed: false
           vuln-type: "os,library"
           severity: ${{ steps.set_severity.outputs.severity }}
+          # The cache update takes quite long, so let's try to disable it for now: https://github.com/aquasecurity/trivy-action#cache
+          cache: 'false'
         continue-on-error: false
 
       - name: Push image