Backend plugins: Refactor to allow shared contract between core and external backend plugins (#25472)

Refactor to allow shared contract between core and external backend plugins 
allowing core backend data sources in Grafana to be implemented in same 
way as an external backend plugin.
Use v0.67.0 of sdk.
Add tests for verifying plugin is restarted when process is killed.
Enable strict linting for backendplugin packages

* Add tracing switch to explore

* Prettify

* Docs: Fix intro to timeseries URL

* Update docs/sources/developers/plugins/data-frames.md

Co-authored-by: Marcus Olsson <accounts+github@marcus.se.net>

Co-authored-by: Marcus Olsson <accounts+github@marcus.se.net>

* Update guide on authenticating data source plugins

* Fix broken references

The existing link for developing plugins was redirecting to the legacy plugin docs page for developers. I updated it to the new link for latest post-7.0 release. 👍

* Update Bitcoin Currency to use proper symbol, add mBTC and μBTC

* Apply suggestions from code review

Co-authored-by: Marcus Andersson <systemvetaren@gmail.com>

* Revert Bitcoin to use '฿'

Co-authored-by: Marcus Andersson <systemvetaren@gmail.com>

dashboard instead of dashboad

* add flux 
* add token to datasource config editor
* add backend for flux
* make the interpolated query available in query inspector
* go mod tidy
* Chore: fixes a couple of strict null errors in influxdb plugin

Co-authored-by: kyle <kyle@grafana.com>
Co-authored-by: Lukas Siatka <lukasz.siatka@grafana.com>

* TextPanel: Removes Angular Text Panel

* Tests: updates snapshots

* Chore: adds core datasources to codeowners

* Chore: updates opentsdb to be under backend platform team

* Fix dense y-axis labels in heatmap using tsbuckets

This change emulates the non-tsbuckets Y-axis tick count by making
the y-axis label formatter treat a dense set as a sparse set.

fixes #11342

* have d3 do the work

* Update public/app/plugins/panel/heatmap/rendering.ts

Co-authored-by: Alexander Zobnin <alexanderzobnin@gmail.com>

Co-authored-by: Alexander Zobnin <alexanderzobnin@gmail.com>

* Table: Adds adhoc filtering

* Refactor: changes after PR comments

* Refactor: hides filtering for data sources that do not support modifyQuery in Explore

* Refactor: fixes strict null error

* Changed tooltip position to above icon

Co-authored-by: Torkel Ödegaard <torkel@grafana.com>

* Plugins: move jaeger trace type to grafana data

* Remove unnecessary type from tsconfig

All screen sizes is correct terminology to use

* Table: Custom date formating via custom unit

* FieldConfig: Changed so that shouldApply is not called for overrides and added unit test

* Updated

* Chore: adds error handling to get requests in elasticsearch datasource

* Chore: updates elasticsearch datasource response parsing checks

* Chore: updates elasticsearch non-json errors description

* Chore: removes error catching from query methods to move it to the request method in elasticsearch

* Chore: fixes a typo in elastic response error message

* Chore: moves elasticsearch error handling to request method

* Chore: replaces datasource url in mock elasticsearch datasource

Be more explicit about the fact that providing images in alert notifications requires an external image storage provider. Previously this read as if it was only necessary for publicly accessible images, but even if they are served from Grafana, the administrator must set up the "local" image provider in the configuration.

Make tsdb dataframes response able to carry encoded and/or decoded frames

* Add metrics and dimensions for AWS/WAFV2

* Update pkg/tsdb/cloudwatch/metric_find_query.go

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

* Fix metric names

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

https://grafana.com/docs/grafana/latest/auth/github/#enable-github-in-grafana

* Update stackdriver.md

* Update stackdriver.md

* Update stackdriver.md

* Update index.md

* Update whats-new-in-v2.md

* Correcting abbreviation

* Update azuread.md

* Update whats-new-in-v6-3.md

* Update enterprise-configuration.md

* Update enterprise-configuration.md