Allow get schedules by name

[jen13501]

Some of our teams use shared schedules that aren't owned by any individual team. This currently isn't supported by the plugin - the schedule is returned by GET /schedules but is filtered out because it doesn't have an owning team. We could adjust our schedules to be owned by one of the teams, but is it useful for others to add a way to select schedules by schedule name instead of team name?
Currently thinking this would be done by adding a second annotation "opsgenie.com/schedule"

[jen13501]

@K-Phoen wanted to follow up on this issue and the related open pull request - is this something the plugin could support?