refactor: Use graphql schema directly with graphql-tools library

packages/backend/package.json

@@ -18,6 +18,8 @@
   },
   "dependencies": {
     "@automatisch/web": "0.1.0",
+    "@graphql-tools/graphql-file-loader": "^7.3.4",
+    "@graphql-tools/load": "^7.5.2",
     "@octokit/oauth-methods": "^1.2.6",
     "ajv-formats": "^2.1.1",
     "axios": "0.24.0",
@@ -34,6 +36,7 @@
     "googleapis": "89.0.0",
     "graphql-middleware": "^6.1.15",
     "graphql-shield": "^7.5.0",
+    "graphql-tools": "^8.2.0",
     "graphql-type-json": "^0.3.2",
     "http-errors": "~1.6.3",
     "jsonwebtoken": "^8.5.1",