Update unicode emoji ver from 12.0 to 12.1

As outlined in ruby/ruby@c54635c08b

"This update does not add any new codepoint assignments, it just
expands the range of emoji codepoint sequences recommended for
public interchange.

Depending on how emoji data files are cached, this commit may
require manual intervention in some build environments
(including some CI systems)."

Author: wildmaples

lib/truffle/rbconfig.rb

@@ -192,7 +192,7 @@ module RbConfig
     'target_cpu'        => host_cpu,
     'target_os'         => host_os,
     'UNICODE_VERSION'   => '12.0.0',
-    'UNICODE_EMOJI_VERSION' => '12.0',
+    'UNICODE_EMOJI_VERSION' => '12.1',
     'warnflags'         => warnflags,
   }