Add custom start date for Faker::Date.forward

[luciagirasoles]

Motivation / Background

The goal of this PR is to make it possible to use a custom start date using the Faker::Date.forward function. Adding this will enable from param to be filled with 'Date.current' from Rails or a String like "Thu, 22 Jun 2023"
Fixes #2093.

Additional information

Checklist

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[thdaraujo]

Thanks for working on this, I think this is a good solution that adds flexibility to this generator.

Left a comment about the test, as I don't think it's necessary to run it 100 times.

[thdaraujo]

LGTM, thank you!

[thdaraujo]

Suggested change

	100.times do
	random_date = @tester.forward(from: from, days: 5)
	assert random_date > from_date, "Expected > \"#{from}\", but got #{random_date}"
	end
	random_date = @tester.forward(from: from, days: 5)
	assert random_date > from_date, "Expected > \"#{from}\", but got #{random_date}"