fix(flatmap-stream): update tsc-watch

flatmap-stream was undeployed in version 0.1.2 because of security issues, tsc-watch was dependent on it. so we had to bumb the version

Author: michaelwittwer

package-lock.json

@@ -76,7 +76,7 @@
     "ts-jest": "^23.10.4",
     "ts-loader": "^5.3.0",
     "ts-node": "^7.0.1",
-    "tsc-watch": "^1.0.30",
+    "tsc-watch": "^1.0.31",
     "tslint": "^5.11.0",
     "tslint-config-prettier": "^1.16.0",
     "typedoc": "^0.13.0",