Update dependency rxjs to v7

Author: renovate-bot

angular-client/package.json

@@ -37,7 +37,7 @@
     "graphql": "^14.0.2",
     "graphql-tag": "^2.10.0",
     "hammerjs": "^2.0.8",
-    "rxjs": "~6.3.3",
+    "rxjs": "~7.0.0",
     "zone.js": "~0.8.26"
   },
   "devDependencies": {