Revert "add workaround for slow podman internal dns resolver"

This reverts commit 3c31de3427.

should use "dns_search: dns.podman" in the override instead

https://github.com/containers/podman/issues/9169#issuecomment-807417455

app/startup.sh

@@ -21,17 +21,6 @@ SRC_REPO=https://git.tt-rss.org/fox/tt-rss.git
 
 export PGPASSWORD=$TTRSS_DB_PASS 
 
-# podman internal dns is hilariously slow
-if [ ! -z "${TTRSS_DB_SLOW_DNS_HACK}" ]; then
-	DBIPADDR=$(ping -c 1 db | grep from | cut -d " " -f 4 | tr -d :)
-
-	if [ ! -z "$DBIPADDR" ]; then
-		echo overriding DB host with IP address: $DBIPADDR
-		export TTRSS_DB_HOST=$DBIPADDR
-	fi
-fi
-
-
 [ ! -e /var/www/html/index.php ] && cp ${SCRIPT_ROOT}/index.php /var/www/html
 
 PSQL="psql -q -h $TTRSS_DB_HOST -U $TTRSS_DB_USER $TTRSS_DB_NAME"