Make PR template instructions even more explicit (opensearch-project#10565)

* Make PR template instructions even more explicit

Signed-off-by: kolchfa-aws <[email protected]>

* Update .github/PULL_REQUEST_TEMPLATE.md

Signed-off-by: kolchfa-aws <[email protected]>

* Update .github/PULL_REQUEST_TEMPLATE.md

Signed-off-by: Nathan Bower <[email protected]>

---------

Signed-off-by: kolchfa-aws <[email protected]>
Signed-off-by: Nathan Bower <[email protected]>
Co-authored-by: Nathan Bower <[email protected]>

Author: kolchfa-aws

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,7 +2,7 @@
 _Describe what this change achieves._
 
 ### Issues Resolved
-Closes #[_delete this text, including the brackets, and replace with the issue number_]
+Closes #[_Replace this text, including the brackets, with the issue number._ **Leave "Closes #" so the issue is closed properly.**]
 
 ### Version
 _List the OpenSearch version to which this PR applies, e.g. 2.14, 2.12--2.14, or all._