install string-replace-loader devDep

Author: Nikolaos Veneti

package-lock.json

@@ -33,6 +33,7 @@
         "@babel/core": "^7.6.4",
         "@babel/preset-env": "^7.6.3",
         "babel-loader": "^8.0.6",
-        "compression-webpack-plugin": "^3.0.0"
+        "compression-webpack-plugin": "^3.0.0",
+        "string-replace-loader": "^2.2.0"
     }
 }