Fix handling of numeric custom cells in Excel

[TaiWilkin]

Overview

Custom cells can have numeric values. When parsing the sheets, a value
that appears as 130 in the workbook can appear as a float 130.0.

This commit attempts to fix this issue by using an
int(float(x)) nested cast to ensure that the decimal portion is removed.

Note that this will convert all floats to integers when submitted as
custom text. If a contributor would like to submit floats in a custom
text field in the future, we will need to implement that as an
enhancement.

The handling of this was based on the recent fix for number_of_workers.

Connects #1748

Demo

Testing Instructions

NOTE: Custom text indexing can take a minute to run, so wait after adjusting any searchable field.

On develop:

• Run ./scripts/server
• Submit
  Numeric_Custom_List.xlsx
• Process the list using ./tools/batch_process {list_id}
• Login as c2@example.com and navigate to the settings -> embed, then set a width and height so your map preview displays
• Select custom_field as a searchable field.
• Search for 23876. No results will return. Search for 23876.0 and one result should return.
• Deselect custom_field as a searchable field.

On this branch:

• Run ./scripts/server
• Select custom_2 as a searchable field.
• Search for 12345 and one result should return.
• Select custom_field as searchable. Search for 23876 and one result should return.

Checklist

• fixup! commits have been squashed
• CI passes after rebase
• CHANGELOG.md updated with summary of features or fixes, following Keep a Changelog guidelines

[rajadain]

+1 tested, this is working well!

[rajadain]

Consider naming this try_parse_int_from_float since that's what you're getting in the end.

[TaiWilkin]

Updated