Update CHANGELOG.md for 10.8.5

[ci skip]

CHANGELOG.md

@@ -253,6 +253,17 @@ entry.
 - Workhorse to send raw diff and patch for commits.
 
 
+## 10.8.5 (2018-06-21)
+
+### Security (5 changes)
+
+- Fix XSS vulnerability for table of content generation.
+- Update sanitize gem to 4.6.5 to fix HTML injection vulnerability.
+- HTML escape branch name in project graphs page.
+- HTML escape the name of the user in ProjectsHelper#link_to_member.
+- Don't show events from internal projects for anonymous users in public feed.
+
+
 ## 10.8.4 (2018-06-06)
 
 - No changes.