limited the loop to 10 times, max 60 sec wait

entrypoint.sh

@@ -2,9 +2,15 @@ set -e
 
 testConnection="/opt/mssql-tools/bin/sqlcmd -S sql -U sa -P Password123"
 
-until $testConnection; do
+for run in {1..10}; do
+
 >&2 echo "SQL Server is starting up.."
-sleep 1
+if $testConnection; then
+    >&2 echo "SQL Server is up!"
+    break;
+else
+    sleep 6
+fi
 done
 
->&2 echo "SQL Server is up!"
+