[MM-21466] delete users cmd return err (#31191)

* refactored error managment for deleteUsersCmdF

* updated tests related to deleteUsersCmdF

* updated user_e2e_test to reflect changes made to the deleteUsersCmdF function

* Empty-Commit to retrigger workflow

* applied gofmt formating reqs to user_test.go

* added suggested changes to the deleteUsersCmdF regarding error gathering

* added requested changes regarding error aggragation on deleteUsersCmdF

* style(mmctl): removing trailing whitespace

* feat(mmctl): returning errors in deleteUserCmdF on err

* fix(mmctl): returns when err parsing args

* test(mmctl): updated tests to expect err instead of reading printer

* style: updating returned errs

* tests: updated test to reflect error change

* tests(mmctl): updated e2e DeleteUserCmd test

* Update server/cmd/mmctl/commands/user.go

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

* refactor: changing error to return username instead of email

* refactor: changing email to username for errors

---------

Co-authored-by: Arnaud Wanet <andrewwanet9@gmail.com>
Co-authored-by: Antonis Stamatiou <stamatiou.antonis@gmail.com>
Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/cmd/mmctl/commands/user.go

@@ -738,24 +738,30 @@ func deleteUsersCmdF(c client.Client, cmd *cobra.Command, args []string) error {
 
 	users, err := getUsersFromArgs(c, args)
 	if err != nil {
-		printer.PrintError(err.Error())
+		return err
 	}
+
+	var errs *multierror.Error
 	for i, user := range users {
 		if user == nil {
 			printer.PrintError("Unable to find user '" + args[i] + "'")
 			continue
 		}
 		if res, err := c.PermanentDeleteUser(context.TODO(), user.Id); err != nil {
-			printer.PrintError("Unable to delete user '" + user.Username + "' error: " + err.Error())
+			errs = multierror.Append(errs,
+				fmt.Errorf("unable to delete user %s error: %w", user.Username, err))
 		} else {
 			// res.StatusCode is checked for 202 to identify issues with file deletion.
 			if res.StatusCode == http.StatusAccepted {
-				printer.PrintError("There were issues with deleting profile image of the user. Please delete it manually. Id: " + user.Id)
+				errs = multierror.Append(errs,
+					fmt.Errorf("unable to delete the profile image of the user, please delete it manually, id:%s", user.Username))
+				continue
 			}
 			printer.PrintT("Deleted user '{{.Username}}'", user)
 		}
 	}
-	return nil
+
+	return errs.ErrorOrNil()
 }
 
 func deleteAllUsersCmdF(c client.Client, cmd *cobra.Command, args []string) error {