refs #15273 [master-v5]

*concatenate base url and param list correctly for finc Link Resolver
** add ResolverTrait to override method getResolverUrl, improve handling of question marks / anpersand
** use getResolverUrl in finc Ezb
** add finc Redi class and use getResolverUrl of finc trait
** add tests for Ezb and Redi
* improve handling and validation of openUrl parameters
** read static openUrl parameters from Resolver.ini in method addCustomParams
** validate necessary function return values for Ezb and Redi to prevent empty links and calls to resolver service
** add OpenUrlTest for both methods