Add Docker Authentication Testing and Results documentation

README.md

@@ -72,7 +72,7 @@ Both outreach_1 and outreach_2 inherited Runner 1, which was registered with tok
 
 **Result:** ✅ Passed. Both subgroups successfully executed pipelines using the shared runner and token.
 
-Test Case 5: Multi-GitLab Instance Authentication
+**Test Case 5: Multi-GitLab Instance Authentication**
 
 **Objective:** Ensure runners on the same VM can authenticate to separate GitLab instances simultaneously.