plugins: Add template/package-lock.json so npm 7 doesn't get stuck

Additionally we stop using --link inside test-headlamp-plugin.sh
so that it tests more closely what users will run. Previously this
would hang when using npm v7.

Author: illume

plugins/headlamp-plugin/bin/headlamp-plugin.js

@@ -26,6 +26,7 @@ function create(name, link) {
   const templateFolder = path.resolve(__dirname, '..', 'template');
   const indexPath = path.join(dstFolder, 'src', 'index.tsx');
   const packagePath = path.join(dstFolder, 'package.json');
+  const packageLockPath = path.join(dstFolder, 'package-lock.json');
 
   if (fs.existsSync(name)) {
     console.error(`"${name}" already exists, not initializing`);
@@ -51,6 +52,7 @@ function create(name, link) {
   }
 
   replaceFileVariables(packagePath);
+  replaceFileVariables(packageLockPath);
   replaceFileVariables(indexPath);
 
   // This can be used to make testing locally easier.