Log Message:
print/ruby-pdf-reader: update to 2.12.0

2.12.0 (2023-12-26)

* Fix a sorbet method signature (http://github.com/yob/pdf-reader/pull/512)
* Reduce allocations when parsing PDFs with hex strings
  (http://github.com/yob/pdf-reader/pull/528)
* Fix text extraction of some rare unicode codepoints
  (http://github.com/yob/pdf-reader/pull/529)