CHANGELOG.md in numo-libsvm-2.1.1 vs CHANGELOG.md in numo-libsvm-2.2.0

@@ -1,4 +1,7 @@
+# 2.2.0
+- Update bundled LIBSVM to 3.31.
+
 # 2.1.1
 - Fix build failure with Xcode 14 and Ruby 3.1.x.
 
 # 2.1.0
 - Update bundled LIBSVM to 3.30.