Revert "chore: upgrade dev dependencies"

This reverts commit f5868ba.

Author: Matt Lewis

package-lock.json

@@ -109,7 +109,7 @@
     "@types/chai": "^4.1.3",
     "@types/mocha": "^5.2.0",
     "@types/node": "^10.1.2",
-    "@types/sinon": "^5.0.0",
+    "@types/sinon": "^4.3.3",
     "@types/sinon-chai": "^2.7.32",
     "@types/webpack": "^4.4.0",
     "angular-router-loader": "^0.8.5",
@@ -134,7 +134,7 @@
     "istanbul-instrumenter-loader": "^3.0.1",
     "karma": "^2.0.2",
     "karma-chrome-launcher": "^2.1.1",
-    "karma-coverage-istanbul-reporter": "^2.0.1",
+    "karma-coverage-istanbul-reporter": "^1.4.3",
     "karma-mocha": "^1.3.0",
     "karma-mocha-reporter": "^2.2.4",
     "karma-sourcemap-loader": "^0.3.7",