Alerting: Fix unmarshalling of GettableStatus to include time intervals (#112602)

* move test files into test-data

* add test for the bug

* populate time-intervals of gettableStatus config

pkg/services/ngalert/api/tooling/definitions/alertmanager_test.go

@@ -1,8 +1,10 @@
 package definitions
 
 import (
+	"embed"
 	"encoding/json"
-	"os"
+	"path"
+	"reflect"
 	"strings"
 	"testing"
 
@@ -15,6 +17,32 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
+//go:embed test-data/*.*
+var testData embed.FS
+
+func Test_GettableStatusUnmarshalJSON(t *testing.T) {
+	incoming, err := testData.ReadFile(path.Join("test-data", "gettable-status.json"))
+	require.Nil(t, err)
+
+	var actual GettableStatus
+	require.NoError(t, json.Unmarshal(incoming, &actual))
+
+	actualJson, err := json.Marshal(actual)
+	require.NoError(t, err)
+
+	expected, err := testData.ReadFile(path.Join("test-data", "gettable-status-expected.json"))
+	require.NoError(t, err)
+	assert.JSONEq(t, string(expected), string(actualJson))
+
+	v := reflect.ValueOf(actual.Config.Config)
+	ty := v.Type()
+	for i := 0; i < v.NumField(); i++ {
+		field := v.Field(i)
+		fieldName := ty.Field(i).Name
+		assert.False(t, field.IsZero(), "Field %s should not be zero value", fieldName)
+	}
+}
+
 func Test_GettableUserConfigUnmarshaling(t *testing.T) {
 	for _, tc := range []struct {
 		desc, input string
@@ -140,10 +168,10 @@ alertmanager_config: |
 func Test_GettableUserConfigRoundtrip(t *testing.T) {
 	// raw contains secret fields. We'll unmarshal, re-marshal, and ensure
 	// the fields are not redacted.
-	yamlEncoded, err := os.ReadFile("alertmanager_test_artifact.yaml")
+	yamlEncoded, err := testData.ReadFile(path.Join("test-data", "alertmanager_test_artifact.yaml"))
 	require.Nil(t, err)
 
-	jsonEncoded, err := os.ReadFile("alertmanager_test_artifact.json")
+	jsonEncoded, err := testData.ReadFile(path.Join("test-data", "alertmanager_test_artifact.json"))
 	require.Nil(t, err)
 
 	// test GettableUserConfig (yamlDecode -> jsonEncode)
@@ -162,7 +190,7 @@ func Test_GettableUserConfigRoundtrip(t *testing.T) {
 }
 
 func Test_Marshaling_Validation(t *testing.T) {
-	jsonEncoded, err := os.ReadFile("alertmanager_test_artifact.json")
+	jsonEncoded, err := testData.ReadFile(path.Join("test-data", "alertmanager_test_artifact.json"))
 	require.Nil(t, err)
 
 	var tmp GettableUserConfig