browser(unit): update search response for date values
browser(unit): update search response for date values

Date values in facets are now ISO Date strings. Update mocks in tests
to reflect updated format.

dmcassel/marklogic-samplestack,laurelnaiad/marklogic-samplestack,dmcassel/marklogic-samplestack,marklogic/marklogic-samplestack,dmcassel/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,omkarudipi/marklogic-samplestack,marklogic/marklogic-samplestack,marklogic/marklogic-samplestack,marklogic/marklogic-samplestack,laurelnaiad/marklogic-samplestack,laurelnaiad/marklogic-samplestack,omkarudipi/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,ryanjdew/discovery-app-w-samplestack,omkarudipi/marklogic-samplestack,laurelnaiad/marklogic-samplestack,omkarudipi/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,supriyantomaftuh/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,dmcassel/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack