Fix a typo

Follow up of #7869.

config/default.yml

@@ -2838,7 +2838,7 @@ Style/FrozenStringLiteralComment:
     # `always` will always add the frozen string literal comment to a file
     # regardless of the Ruby version or if `freeze` or `<<` are called on a
     # string literal. If you run code against multiple versions of Ruby, it is
-    # possible that this will create errors in Ruby 2.4.0+.
+    # possible that this will create errors in Ruby 2.3.0+.
     - always
     # `always_true` will add the frozen string literal comment to a file,
     # similarly to the `always` style, but will also change any disabled