remove unused istanbul dependency

Author: tiagoschenkel

package.json

@@ -82,7 +82,6 @@
     "glslify": "^7.0.0",
     "html-webpack-plugin": "^3.2.0",
     "imports-loader": "^0.8.0",
-    "istanbul": "^0.4.5",
     "istanbul-instrumenter-loader": "^3.0.1",
     "karma": "^4.4.1",
     "karma-chrome-launcher": "^3.1.0",

yarn.lock

@@ -3840,7 +3840,7 @@ istanbul-reports@^2.2.4:
   dependencies:
     handlebars "^4.1.2"
 
-[email protected], istanbul@^0.4.5:
+[email protected]:
   version "0.4.5"
   resolved "https://registry.npmjs.org/istanbul/-/istanbul-0.4.5.tgz#65c7d73d4c4da84d4f3ac310b918fb0b8033733b"
   integrity sha1-ZcfXPUxNqE1POsMQuRj7C4Azczs=