WIP: better test coverage for the Trigger class; adding test stubs for some of our recurrence requirements
WIP: better test coverage for the Trigger class; adding test stubs for some of our recurrence requirements

tndatacommons/tndata_backend,izzyalonso/tndata_backend,tndatacommons/tndata_backend,tndatacommons/tndata_backend,izzyalonso/tndata_backend,tndatacommons/tndata_backend,izzyalonso/tndata_backend,izzyalonso/tndata_backend