Made log part of the PR comment collapsable.

Author: gkistanova

zorg/buildbot/reporters/utils.py

@@ -136,10 +136,14 @@ def get_log_details(build):
 
 Full details are available at: {{ build_url }}
 
-Here is the relevant piece of the build log for the reference:
+<details>
+<summary>Here is the relevant piece of the build log for the reference</summary>
+
 ```
 {{ details }}
 ```
+
+</details>
 """