Update default gems list at 874469e [ci skip]

Author: matzbot

NEWS.md

@@ -72,7 +72,7 @@ The following default gems are updated.
 * RubyGems 3.7.0.dev
 * bundler 2.7.0.dev
 * erb 5.0.1
-* json 2.12.0
+* json 2.12.2
 * optparse 0.7.0.dev.2
 * prism 1.4.0
 * psych 5.2.6