Update dependency vue-loader to v15.9.7

Author: renovate-bot

package-lock.json

@@ -36,7 +36,7 @@
     "script-ext-html-webpack-plugin": "2.1.5",
     "start-server-and-test": "1.12.2",
     "vue": "2.6.12",
-    "vue-loader": "15.9.6",
+    "vue-loader": "15.9.7",
     "vue-template-compiler": "2.6.12",
     "webpack": "4.46.0",
     "webpack-cli": "3.3.12",