OAuth: Introduce user_refresh_token setting and make it default for the selected providers (#71533)

* First changes

* WIP docs

* Align current tests

* Add test for UseRefreshToken

* Update docs

* Fix

* Remove unnecessary AuthCodeURL from generic_oauth

* Change GitHub to disable use_refresh_token by default

conf/defaults.ini

@@ -600,6 +600,8 @@ tls_skip_verify_insecure = false
 tls_client_cert =
 tls_client_key =
 tls_client_ca =
+# GitHub OAuth apps does not provide refresh tokens and the access tokens never expires.
+use_refresh_token = false
 
 #################################### GitLab Auth #########################
 [auth.gitlab]
@@ -625,6 +627,7 @@ tls_client_cert =
 tls_client_key =
 tls_client_ca =
 use_pkce = true
+use_refresh_token = true
 
 #################################### Google Auth #########################
 [auth.google]
@@ -647,6 +650,7 @@ tls_client_cert =
 tls_client_key =
 tls_client_ca =
 use_pkce = true
+use_refresh_token = true
 
 #################################### Grafana.com Auth ####################
 # legacy key names (so they work in env variables)
@@ -657,6 +661,7 @@ client_id = some_id
 client_secret =
 scopes = user:email
 allowed_organizations =
+use_refresh_token = false
 
 [auth.grafana_com]
 name = Grafana.com
@@ -669,6 +674,7 @@ client_secret =
 scopes = user:email
 allowed_organizations =
 skip_org_role_sync = false
+use_refresh_token = false
 
 #################################### Azure AD OAuth #######################
 [auth.azuread]
@@ -694,6 +700,7 @@ tls_client_key =
 tls_client_ca =
 use_pkce = true
 skip_org_role_sync = false
+use_refresh_token = true
 
 #################################### Okta OAuth #######################
 [auth.okta]
@@ -719,6 +726,7 @@ tls_client_cert =
 tls_client_key =
 tls_client_ca =
 use_pkce = true
+use_refresh_token = false
 
 #################################### Generic OAuth #######################
 [auth.generic_oauth]
@@ -756,6 +764,7 @@ use_pkce = false
 auth_style =
 allow_assign_grafana_admin = false
 skip_org_role_sync = false
+use_refresh_token = false
 
 #################################### Basic Auth ##########################
 [auth.basic]