Add better resolve alias matching for @vue/compat

The current example needs to be revised since Vite will use the string `vue` to match any import that contains it. (e.g. `import '@vue/server-renderer'` will be transformed to `import '@vue/compat/server-renderer'`

Author: gionkunz

src/migration-build.md

@@ -136,7 +136,7 @@ The following workflow walks through the steps of migrating an actual Vue 2 app
    export default {
      resolve: {
        alias: {
-         vue: '@vue/compat'
+         '^vue$': '@vue/compat'
        }
      },
      plugins: [