chore: introduce no-git-conflict-marker rule

Author: lumirlumir

eslint.config.mjs

@@ -10,6 +10,7 @@ export default [
     files: ['src/content/**/*.md'],
     rules: {
       'mark/no-double-space': 'error',
+      'mark/no-git-conflict-marker': ['error', {skipCode: false}],
     },
   },
 ];

src/content/blog/2024/12/05/react-19.md

@@ -4,7 +4,7 @@ author: The React Team
 date: 2024/12/05
 description: React 19 is now available on npm! In this post, we'll give an overview of the new features in React 19, and how you can adopt them.
 ---
-<!-- eslint-disable mark/no-double-space -->
+{/*<!-- eslint-disable mark/no-double-space -->*/}
 December 05, 2024 by [The React Team](/community/team)
 
 ---

src/content/learn/installation.md

@@ -68,7 +68,6 @@ If a framework is not a good fit for your project, you prefer to build your own
 No. Create React App has been deprecated. For more information, see [Sunsetting Create React App](/blog/2025/02/14/sunsetting-create-react-app).
 
 </Note>
->>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff
 
 ## 다음 단계 {/*next-steps*/}