[MM-19740] Return error for non-system-admins/team admins/channel admins from the GET /api/v4/groups API endpoint response (#12961)

* [MM-19740] Differentiate between admin and non-admin

* [MM-19740] added testing admin and non admin

* [MM-19740] Address PR comments

* [MM-19740] Addressed PR comments

* [MM-19740] Updated en.json

* [MM-19740] Addressed PR comments

* Address PR comments

* Address PR comments

api4/group.go

@@ -575,23 +575,40 @@ func getGroups(c *Context, w http.ResponseWriter, r *http.Request) {
 		c.Err = model.NewAppError("Api4.getGroups", "api.ldap_groups.license_error", nil, "", http.StatusNotImplemented)
 		return
 	}
+	var teamID, channelID string
+
+	if id := c.Params.NotAssociatedToTeam; model.IsValidId(id) {
+		teamID = id
+	}
+
+	if id := c.Params.NotAssociatedToChannel; model.IsValidId(id) {
+		channelID = id
+	}
+
+	if teamID == "" && channelID == "" {
+		c.Err = model.NewAppError("Api4.getGroups", "api.getGroups.invalid_or_missing_channel_or_team_id", nil, "", http.StatusBadRequest)
+		return
+	}
 
 	opts := model.GroupSearchOpts{
 		Q:                  c.Params.Q,
 		IncludeMemberCount: c.Params.IncludeMemberCount,
 	}
 
-	teamID := c.Params.NotAssociatedToTeam
-	if len(teamID) == 26 {
-		if !c.App.SessionHasPermissionToTeam(c.App.Session, teamID, model.PERMISSION_VIEW_TEAM) {
-			c.SetPermissionError(model.PERMISSION_VIEW_TEAM)
+	if teamID != "" {
+		_, err := c.App.GetTeam(teamID)
+		if err != nil {
+			c.Err = err
+			return
+		}
+		if !c.App.SessionHasPermissionToTeam(c.App.Session, teamID, model.PERMISSION_MANAGE_TEAM) {
+			c.SetPermissionError(model.PERMISSION_MANAGE_TEAM)
 			return
 		}
 		opts.NotAssociatedToTeam = teamID
 	}
 
-	channelID := c.Params.NotAssociatedToChannel
-	if len(channelID) == 26 {
+	if channelID != "" {
 		channel, err := c.App.GetChannel(channelID)
 		if err != nil {
 			c.Err = err