[ruby/irb] Bump version to 1.7.2

(https://github.com/ruby/irb/pull/636)

https://github.com/ruby/irb/commit/85d6b4d146

lib/irb/version.rb

@@ -5,7 +5,7 @@
 #
 
 module IRB # :nodoc:
-  VERSION = "1.7.1"
+  VERSION = "1.7.2"
   @RELEASE_VERSION = VERSION
-  @LAST_UPDATE_DATE = "2023-07-01"
+  @LAST_UPDATE_DATE = "2023-07-12"
 end