Use a specific ytdl version

requirements.txt

@@ -1,7 +1,7 @@
 python-telegram-bot
 flask
 sqlalchemy
-youtube-dl
+youtube_dl==2019.02.18
 requests
 psycopg2-binary
 PyNaCl

update.sh

@@ -6,7 +6,7 @@ git stash
 git pull
 git lfs pull
 new=$(git rev-list HEAD -n 1)
-if [ ${old} = ${new} ]; then
+if [[ ${old} = ${new} ]]; then
         version=$(sentry-cli releases propose-version)
         sentry-cli releases new -p royalnet ${version}
         sentry-cli releases set-commits --auto ${version}