Display issue with the scroll bar in the data source schema

[madalincm]

Steps to Reproduce:

1. Open new query page: https://pipeline-sql.stage.mozaws.net/queries/new
2. Select Athena as the data source and refresh the schema
3. Observe the layout of the data source schema

Expected results:

There are no layout issues

Actual results:

The scroll bar inside the data source schema is displayed outside the box

Notes/Issues:

Build identifier: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:58.0) Gecko/20100101 Firefox/58.0
Verified in FF58(Win7). Issue can be reproduced in STMO-stage

[madalincm]

Verified in FF58(Win7x64) in stmo-stage
The issue is no longer reproducing:

Closing and marking as verified fixed.