Update pull_request_template.md

Fixed the 404 link to Create learning path

Author: pareenaverma

.github/pull_request_template.md

@@ -1,5 +1,5 @@
 
-Before submitting a pull request for a new Learning Path, please review [Create a Learning Path](https://learn.arm.com//learning-paths/cross-platform/_example-learning-path/)
+Before submitting a pull request for a new Learning Path, please review [Create a Learning Path](https://learn.arm.com/learning-paths/cross-platform/_example-learning-path/)
 - [ ] I have reviewed Create a Learning Path
 
 Please do not include any confidential information in your contribution. This includes confidential microarchitecture details and unannounced product information.