fix: package.json & yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-ANSIREGEX-1583908

package.json

@@ -28,18 +28,18 @@
     "graphql-relay": "^0.6.0",
     "graphql-resolve-batch": "^1.0.2",
     "graphql-subscriptions": "^1.0.0",
-    "grpc": "^1.24.3",
+    "grpc": "^1.24.8",
     "js-xdr": "^1.1.0",
     "minimist": "^1.2.3",
     "object-dig": "^0.1.3",
     "pg": "^8.2.1",
-    "pg-monitor": "^1.1.0",
+    "pg-monitor": "^1.5.0",
     "pg-promise": "^8.7.4",
     "progress": "^2.0.3",
     "retry": "^0.12.0",
     "squel": "^5.12.2",
     "stellar-base": "^3.0.4",
-    "typeorm": "^0.2.17",
+    "typeorm": "^0.2.39",
     "typescript-memoize": "^1.0.0-alpha.3",
     "winston": "^3.0.0"
   },