Support ruby 3

[jrafanie]

• rspec-mocks 3.10.3 requires "with" to be explicit with hashes vs. kwargs
• Handle ruby 2.6-3.0+ kwargs/options Change execute_with_user to capture any kwargs passed as a hash and append to args passed in and call the MiqAeServiceMethods method with these args but never send over the kwargs. Therefore all MiqAeServiceMethods methods can be made to only accept options hashes and never kwargs. This works with ruby 2.6-3.0+. We can change this when we drop ruby 2.
• Add tests for methods to exercise ruby 3/2 args
• Fix bug where conditional is always true, and handling nil/empty array

[jrafanie]

cc @Fryguy do you have opinions about using the ruby2_keywords for the very open ended execute methods that users can be using with old style interfaces. It requires we drop ruby 2.6 here but I think that's what we're doing anyway.