build(v1.8.0-RC5): update changelog

Author: evegufy

CHANGELOG.md

@@ -2,11 +2,16 @@
 
 New features, fixed bugs, known defects and other noteworthy changes to each release of the Catena-X Portal Assets.
 
-## unreleased 1.8.0-RC5
+## 1.8.0-RC5
+
+### Change
+
+- improved offer release process documentation
+- updated security assessment
 
 ### Bugfix
 
-- fixed links in documentation pages
+- fixed links (relative links, image links and links to GitHub) in documentation app
 
 ## 1.8.0-RC4