chore: update PULL_REQUEST_TEMPLATE.md - add changelog instead of det…

…ailed description (SigmaHQ#4386)

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,19 +1,31 @@
 <!--
-Thanks for your contribution. Please make sure to fill the contents of this template with the necessary information to ease and speed up the review process. PLEASE DO NOT DELETE ANY SECTION OR THE CONTENT OF THE TEMPLATE.
+Thanks for your contribution. Please make sure to fill the contents of this template with the necessary information to ease and speed up the review process.
+
+!!! PLEASE DO NOT DELETE ANY SECTION, COMMENT OR THE CONTENT OF THE TEMPLATE. !!!
 -->
 
 ### Summary of the Pull Request
 
 <!--
-**Please note that this Section is required and must be filled**
+**Please note that this section is required and must be filled**
 A short summary of your pull request. 
 -->
 
-### Detailed Description of the Pull Request / Additional Comments
+### Changelog
 
 <!--
-**Please note that this Section is required and must be filled**
-A detailed description of the pull request and any additional comments or context.
+** Don't remove this comment **
+You need to add one line for every changed file of the PR and prefix one of the following tags:
+- new:	<title>
+- update:	<title> - <optional comment>
+- fix:	<title> - <optional comment>
+- chore: for non-detection related changes (e.g. dates/titles) and changes on workflow
+
+e.g.
+- new: Brute-Force Attacks on Azure Admin Account
+- update: Suspicious Microsoft Office Child Process - add MSPUB.EXE
+- fix: Malware User Agent - remove legitimate Firefox UA
+- chore: workflow - update checkout version
 -->
 
 ### Example Log Event