chore: Update Shopware 6.5.7 tag to v6.5.7.3

Author: aragon999

.github/workflows/build-docker-images.yaml

@@ -203,7 +203,7 @@ jobs:
             php-version: "8.1"
             flavour: alpine
             template: https://github.com/shopware/shopware
-          - shopware-version: v6.5.7.2
+          - shopware-version: v6.5.7.3
             php-version: "8.1"
             flavour: alpine
             template: https://github.com/shopware/shopware
@@ -331,7 +331,7 @@ jobs:
             php-version: "8.1"
             flavour: bullseye
             template: https://github.com/shopware/shopware
-          - shopware-version: v6.5.7.2
+          - shopware-version: v6.5.7.3
             php-version: "8.1"
             flavour: bullseye
             template: https://github.com/shopware/shopware