Fixed CLA link

Author: ezimuel

.github/PULL_REQUEST_TEMPLATE.md

@@ -3,12 +3,12 @@
 Thanks for the Pull Request!  Before you submit the PR, please
 look over this checklist:
 
-- Have you signed [Contributor License Agreement](http://www.elasticsearch.org/contributor-agreement/)?
+- Have you signed [Contributor License Agreement](https://www.elastic.co/contributor-agreement)?
 PR's (no matter how small) cannot be merged until the CLA has been signed.  It only needs to be signed once,
 however.
 
 - Have you read the [Contributing Guidelines](https://github.com/elastic/elasticsearch-php/blob/master/.github/CONTRIBUTING.md)?
 
 If you answered yes to both, thanks for the PR and we'll get to it ASAP! :)
 
--->
+-->