OAuth: Allow assigning Server Admin (#54780)

* extract errors to errors file

* implement oauth server admin assignment

* add server admin tests

* deduplicate autoAssignOrgRole

* deduplicate strict setting

* deduplicate strict setting

* add support for generic oauth

* add role attribute strict support for generic oauth

* add support for github/gitlab

* assignGrafanaAdmin option is here to stay

* unify similar errors

* add config option

* add okta server admin mapping

* remove never used Company attribute

* unify generic oauth role extract with other methods

* case insensitive role match as in azure

* add ini settings

* add server admin to devenv

* remove duplicate fields

* add documentation to oauth

* fix titlecase test

* implement doc feedback

conf/sample.ini

@@ -473,6 +473,9 @@
 ;allowed_domains =
 ;team_ids =
 ;allowed_organizations =
+;role_attribute_path =
+;role_attribute_strict = false
+;allow_assign_grafana_admin = false
 
 #################################### GitLab Auth #########################
 [auth.gitlab]
@@ -486,6 +489,9 @@
 ;api_url = https://gitlab.com/api/v4
 ;allowed_domains =
 ;allowed_groups =
+;role_attribute_path =
+;role_attribute_strict = false
+;allow_assign_grafana_admin = false
 
 #################################### Google Auth ##########################
 [auth.google]
@@ -522,6 +528,7 @@
 ;allowed_domains =
 ;allowed_groups =
 ;role_attribute_strict = false
+;allow_assign_grafana_admin = false
 
 #################################### Okta OAuth #######################
 [auth.okta]
@@ -538,6 +545,7 @@
 ;allowed_groups =
 ;role_attribute_path =
 ;role_attribute_strict = false
+;allow_assign_grafana_admin = false
 
 #################################### Generic OAuth ##########################
 [auth.generic_oauth]
@@ -570,6 +578,7 @@
 ;tls_client_ca =
 ;use_pkce = false
 ;auth_style =
+;allow_assign_grafana_admin = false
 
 #################################### Basic Auth ##########################
 [auth.basic]