remove export for HPB domain

It's not needed to export the `HPB_DOMAIN` as that would mean it's the same as `NC_DOMAIN`, which is not the case if `HPB_DOMAIN` is used. 

Was a bit to quick when reviewing, sorry.

Signed-off-by: Daniel Hansson <mailto@danielhansson.nu>

Containers/talk-recording/start.sh

@@ -12,10 +12,6 @@ elif [ -z "$INTERNAL_SECRET" ]; then
     exit 1
 fi
 
-if [ -z "$HPB_DOMAIN" ]; then
-    export HPB_DOMAIN="$NC_DOMAIN"
-fi
-
 cat << RECORDING_CONF > "/conf/recording.conf"
 [logs]
 # 30 means Warning