chore: tweak changelog format

KazuCocoa · KazuCocoa · commit 14590cce6f6c · 2024-05-19T21:15:13.000-07:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,7 +4,7 @@ Commit based release not is [release_notes.md](./release_notes.md)
 Release tags are https://github.com/appium/ruby_lib/releases .
 
 
-## [15.1.0] - 2024-05-19
+## 15.1.0 - 2024-05-19
 - Use appium_lib_core 9.0.0
 
 ## 15.0.1 - 2024-04-26
