grafana-iam: Implement resourcepermission update (#110891)

* first go at update implementation

* template tests

* SQL tests

* more tests

* set namespace for read resource permissions

* fix a bug with perms being removed right after they're added

* remove unwanted changes

* fix tests and check error

* PR feedback

* Update pkg/registry/apis/iam/resourcepermission/sql.go

---------

Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>

pkg/registry/apis/iam/resourcepermission/testdata/mysql--permission_remove-remove_permission.sql

@@ -0,0 +1,9 @@
+DELETE FROM `grafana`.`permission` AS p
+WHERE p.scope = 'folders:uid:folder1' AND p.action = 'folders:edit'
+AND p.role_id = (
+    SELECT r.id
+    FROM `grafana`.`role` AS r
+    WHERE r.org_id = 55
+    AND r.name = 'managed:users:1:permissions'
+    LIMIT 1
+)

pkg/registry/apis/iam/resourcepermission/testdata/postgres--permission_remove-remove_permission.sql

@@ -0,0 +1,9 @@
+DELETE FROM "grafana"."permission" AS p
+WHERE p.scope = 'folders:uid:folder1' AND p.action = 'folders:edit'
+AND p.role_id = (
+    SELECT r.id
+    FROM "grafana"."role" AS r
+    WHERE r.org_id = 55
+    AND r.name = 'managed:users:1:permissions'
+    LIMIT 1
+)

pkg/registry/apis/iam/resourcepermission/testdata/sqlite--permission_remove-remove_permission.sql

@@ -0,0 +1,9 @@
+DELETE FROM "grafana"."permission" AS p
+WHERE p.scope = 'folders:uid:folder1' AND p.action = 'folders:edit'
+AND p.role_id = (
+    SELECT r.id
+    FROM "grafana"."role" AS r
+    WHERE r.org_id = 55
+    AND r.name = 'managed:users:1:permissions'
+    LIMIT 1
+)