MM-22783: Fix scopelint issues (#13969)

* Fix scopelint issues

* Incorporating review comments

* Keeping the order of linters alphabetical

* Fix issues after merge

Co-authored-by: mattermod <mattermod@users.noreply.github.com>

store/sqlstore/channel_store.go

@@ -2545,7 +2545,8 @@ func (s SqlChannelStore) MigrateChannelMembers(fromChannelId string, fromUserId
 		return nil, nil
 	}
 
-	for _, member := range channelMembers {
+	for i := range channelMembers {
+		member := channelMembers[i]
 		roles := strings.Fields(member.Roles)
 		var newRoles []string
 		if !member.SchemeAdmin.Valid {