prosody: always rebuild configs on start

Fixes the upgrade which enabled XMPP websockets in the web config
but the necessary changes in the prosody config weren't applied.

prosody/rootfs/etc/cont-init.d/10-config

@@ -25,7 +25,6 @@ if [[ "$(stat -c %U /prosody-plugins-custom)" != "prosody" ]]; then
     chown -R prosody /prosody-plugins-custom
 fi
 
-if [[ ! -f $PROSODY_CFG ]]; then
 cp -r /defaults/* /config
 tpl /defaults/prosody.cfg.lua > $PROSODY_CFG
 tpl /defaults/conf.d/jitsi-meet.cfg.lua > /config/conf.d/jitsi-meet.cfg.lua
@@ -76,7 +75,6 @@ if [[ ! -f $PROSODY_CFG ]]; then
     fi
     prosodyctl --config $PROSODY_CFG register $JIGASI_XMPP_USER $XMPP_AUTH_DOMAIN $JIGASI_XMPP_PASSWORD
 fi
-fi
 
 mkdir -p /config/certs