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

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

pkg/services/ngalert/api/api_ruler_test.go

@@ -60,7 +60,7 @@ func TestRouteDeleteAlertRules(t *testing.T) {
 		deleteCommands := getRecordedCommand(ruleStore)
 		require.Len(t, deleteCommands, 1)
 		cmd := deleteCommands[0]
-		actualUIDs := cmd.Params[2].([]string)
+		actualUIDs := cmd.Params[3].([]string)
 		require.Len(t, actualUIDs, len(expectedRules))
 		for _, rule := range expectedRules {
 			require.Containsf(t, actualUIDs, rule.UID, "Rule %s was expected to be deleted but it wasn't", rule.UID)