chore: prevent null loading sync settings (#17430)

Nulls passed to the frontend caused a page to fail to load.

`Record<string,string>` can be `nil` in golang

coderd/idpsync/group.go

@@ -268,6 +268,9 @@ func (s *GroupSyncSettings) Set(v string) error {
 }
 
 func (s *GroupSyncSettings) String() string {
+	if s.Mapping == nil {
+		s.Mapping = make(map[string][]uuid.UUID)
+	}
 	return runtimeconfig.JSONString(s)
 }
 

coderd/idpsync/organization.go

@@ -217,6 +217,9 @@ func (s *OrganizationSyncSettings) Set(v string) error {
 }
 
 func (s *OrganizationSyncSettings) String() string {
+	if s.Mapping == nil {
+		s.Mapping = make(map[string][]uuid.UUID)
+	}
 	return runtimeconfig.JSONString(s)
 }
 

coderd/idpsync/role.go

@@ -286,5 +286,8 @@ func (s *RoleSyncSettings) Set(v string) error {
 }
 
 func (s *RoleSyncSettings) String() string {
+	if s.Mapping == nil {
+		s.Mapping = make(map[string][]string)
+	}
 	return runtimeconfig.JSONString(s)
 }