build(npm): add ts-toolbelt to devDependencies

npm/ng-packs/package.json

@@ -83,6 +83,7 @@
     "snq": "^1.0.3",
     "symlink-manager": "^1.4.2",
     "ts-node": "~7.0.0",
+    "ts-toolbelt": "^6.3.6",
     "tsickle": "^0.37.0",
     "tslint": "~5.20.0",
     "typescript": "~3.5.3",

npm/ng-packs/yarn.lock

@@ -11685,6 +11685,11 @@ ts-node@~7.0.0:
     source-map-support "^0.5.6"
     yn "^2.0.0"
 
+ts-toolbelt@^6.3.6:
+  version "6.3.6"
+  resolved "https://registry.yarnpkg.com/ts-toolbelt/-/ts-toolbelt-6.3.6.tgz#2bde29106c013ed520c32f30e1248daf8fd4f5f9"
+  integrity sha512-eVzym+LyQodOCfyVyQDQ6FGYbO2Xf9Nc4dGLRKlKSUpAs+8qQWHG+grDiA3ciEuNPNZ0qJnNIYkdqBW1rCWuUA==
+
 tsickle@^0.37.0:
   version "0.37.1"
   resolved "https://registry.yarnpkg.com/tsickle/-/tsickle-0.37.1.tgz#2f8a87c1b15766e866457bd06fb6c0e0d84eed09"