[Fixes #62335952] Correctly check existance of oracle tables and views.

 - Chorus could not validate the existance of oracle tables/views with lowercase names using Sequel constructed queries
 - Sequel (by default) quotes identifier names (great) but all upcases them (defeating the use of quoting for case sensitive matching)
 - Setting :identifier_input_method = nil when creating a Sequel connection disables the upcase of identifier names