Date widget does not display for Agreement lines in Agreement edit view

Overview:
Steps to Reproduce:

1. Create an agreement
2. Note that while creating the agreement, the date picker in the Period Start date works as expected
3. Add an agreement line
4. Go to the Agreement edit view
5. Click the "Active from" or "Active to" date picker

Expected Results:
Date picker widget displays

Actual Results:
Date picker widget does not display