AzureMonitor: Fix logs query multi-resource and timespan values (#67914)
* Update TimeGrain interface methods
- Make them util functions because it's simpler
* Update logs ds to appropiately set resources and timespan
* Set timespan using RCF times
* Update tests
(cherry picked from commit 9d16718acc)
Co-authored-by: Andreas Christou <andreas.christou@grafana.com>
Grot (@grafanabot)
Andres Martinez Gotor