Log Message:
ruby-nokogiri: update to 1.16.3.

Upstream changes:
 https://github.com/sparklemotion/nokogiri/releases/tag/v1.16.3

Dependencies

 * [CRuby] Vendored libxml2 is updated to v2.12.6 from v2.12.5. (@flavorjones)

Changed

 * [CRuby] XML::Reader sets the @encoding instance variable during reading if
   it is not passed into the initializer. Previously, it would remain nil. The
   behavior of Reader#encoding has not changed. This works around changes to
   how libxml2 reports the encoding used in v2.12.6.