Alerting: Allow administrators delete rules permanently via UI (#101974)

* add query parameter to existing APIs to control the permanent deletion of rules
* add GUID to gettable rule
* add new endpoint /ruler/grafana/api/v1/trash/rule/guid/{RuleGUID} to delete rules from trash permanently

---------

Signed-off-by: Yuri Tseretyan <yuriy.tseretyan@grafana.com>

pkg/tests/apis/alerting/notifications/timeinterval/timeinterval_test.go

@@ -660,7 +660,7 @@ func TestIntegrationTimeIntervalReferentialIntegrity(t *testing.T) {
 
 	folderUID := "test-folder"
 	legacyCli.CreateFolder(t, folderUID, "TEST")
-	_, status, data := legacyCli.PostRulesGroupWithStatus(t, folderUID, &ruleGroup)
+	_, status, data := legacyCli.PostRulesGroupWithStatus(t, folderUID, &ruleGroup, false)
 	require.Equalf(t, http.StatusAccepted, status, "Failed to post Rule: %s", data)
 
 	currentRoute := legacyCli.GetRoute(t)