ConfirmModal: Ignore case for confirmation text

[ashharrison90]

What is this feature?

• ignores case when checking the confirmation text
• adds some quotes around the confirmation text
• adds a couple of unit tests to prevent regressions in behaviour

Why do we need this feature?

• slightly easier to use

Who is this feature for?

• everyone

Which issue(s) does this PR fix?:

Fixes #

Special notes for your reviewer:

Please check that:

• It works as expected from a user's perspective.
• If this is a pre-GA feature, it is behind a feature toggle.
• The docs are updated, and if this is a notable improvement, it's added to our What's New doc.