Disable selecting enterprise plugins with no license (#28758)

* Add unlicensed property to plugins

* Disable selecting unlicensed plugin

* Add customizable plugin market place url

* License: workaround enabled only in enterprise

* linter

* Move licensing info to front end

* Update pkg/services/licensing/oss.go

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

* Update pkg/services/licensing/oss.go

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

* Update pkg/setting/setting.go

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

* Update pkg/setting/setting.go

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

* Update pkg/api/frontendsettings.go

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

* Update sample.ini

* Update docs

* Update packages/grafana-runtime/src/config.ts

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

* Update public/app/features/datasources/state/buildCategories.ts

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

* Update pkg/api/frontendsettings.go

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

* Update pkg/setting/setting.go

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

* Fix spelling

Co-authored-by: Leonard Gram <leo@xlson.com>
Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>
Co-authored-by: Torkel Ödegaard <torkel@grafana.org>

pkg/api/plugins.go

@@ -8,7 +8,6 @@ import (
 	"time"
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend"
-
 	"github.com/grafana/grafana/pkg/api/dtos"
 	"github.com/grafana/grafana/pkg/bus"
 	"github.com/grafana/grafana/pkg/models"