Forms and Data Handling: fix: specify that 'empty strings' will be ignored with { value : falsy }

[GaneshS288]

Because

The explaination for optional modifer of express validator left out that empty strings will also be ignored with { value: falsy }

This PR

Changes this line

• This is because { values: "falsy" } means values that aren’t undefined, null, false, or 0 will still be validated.

To this

• This is because { values: "falsy" } means values that aren’t undefined, null, false, 0 or empty strings will still be validated.

Issue

Closes #XXXXX

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[GaneshS288]

@wise-king-sullyman yeah your suggestion is reasonable. I committed it since I think "empty strings ''" is more explicit than just "empty strings". Oops I replied here instead of the original thread since it closed after commit and I couldn't open it again, sorry about that