Fix slack api changes

bridge/slack/slack.go

@@ -156,7 +156,7 @@ func (b *Bslack) JoinChannel(channel config.ChannelInfo) error {
 
 	// try to join a channel when in legacy
 	if b.legacy {
-		_, err := b.sc.JoinChannel(channel.Name)
+		_, _, _, err := b.sc.JoinConversation(channel.Name)
 		if err != nil {
 			switch err.Error() {
 			case "name_taken", "restricted_action":

bridge/slack/users_channels.go

@@ -283,7 +283,7 @@ func (b *channels) populateChannels(wait bool) {
 	// We only retrieve public and private channels, not IMs
 	// and MPIMs as those do not have a channel name.
 	queryParams := &slack.GetConversationsParameters{
-		ExcludeArchived: "true",
+		ExcludeArchived: true,
 		Types:           []string{"public_channel,private_channel"},
 	}
 	for {