Small tweaks to initial form

[Ben-Hodgkiss]

We know there will be possibly bigger changes coming to the initial form given column mappings in Check and the user research being concluded. Until then, we should make the following two smaller changes just to see us through:

• Default the authoritative source question to "Yes"
• Add the Max Batch Size parameter for Arcgis plug-ins so we can unblock a ticket

For the moment, just add the new question to the bottom of the form - we will iterate going forward the actual design.

[paris-dp]

Discussed in refinement- Max batch to be applied for super user accounts only as this will only apply when dev have looked into the problem and confirmed it is due to batch size parameter.

[Ben-Hodgkiss]

Add another new parameter from #590 for page_size. This is for WFS endpoints and will need to be added to the async params too. As with max batch, this should only be able to be edited by super user accounts initially.