⬇️(dependency) downgrade workbox-webpack-plugin to 7.1.0

In the 1.8.0 we experienced issues with the service
worker not updating properly. We suspect that the
workbox-webpack-plugin is the cause of this issue.
Better to downgrade to the last version that worked
until we have time to investigate the issue.
We add workbox-webpack-plugin to the renovate.json
file to avoid future updates.

renovate.json

@@ -13,7 +13,13 @@
       "enabled": false,
       "groupName": "ignored js dependencies",
       "matchManagers": ["npm"],
-      "matchPackageNames": ["fetch-mock", "node", "node-fetch", "eslint"]
+      "matchPackageNames": [
+        "fetch-mock",
+        "node",
+        "node-fetch",
+        "eslint",
+        "workbox-webpack-plugin"
+      ]
     }
   ]
 }