* Loki: Label browser
- replaces stream cascader widget which made it hard to find relevant streams
- multi-step selection allows for selecting a couple of labels first, then find the relevant values
- supports facetting which makes impossible label combinations hard to choose
* Remove unused label hook
* Remove unused label styles
* Use global time range for metadata requests
* Preselect labels if not many exist
* Status and error messages
* Status fixes
* Remove unused import
* Added logs rate button
* Close popup when clicked outside (not working for timepicker :( )
* Change button label
* Get rid of popup and render browser inline
* Review feedback
* Wrap label values and prevent empty lists
Co-authored-by: Zoltán Bedi <zoltan.bedi@gmail.com>
* Explore: Remove datasource testing on selector
- datasource testing gets in the way of fast query iteration: switching
between datasources can take seconds
- it should not be explore's duty to test datasources in the first place
- removed the concept of datasourceError in Explore, should not be its
concern
- datasource erorrs will express themselves in query errors just fine
- connection errors are still bubbled up
- removed reconnection logic from explore, should not be its concern
- missing labels in loki are still "visible" via an empty label selector
- Loki and Prometheus treated connection errors differently than other
datasources, making sure to pass through the original error message
* Show datasource error in query field for prom/loki/influx
* Removed connection test case, fixed disabled state
