fix #15252 - compare 000012345 and 12345

[Izopi4a]

Hello!

• Type: bug fix
• Link to issue: form validation Confirmation strict comparison  #15252

In raising this pull request, I confirm the following:

• I have read and understood the Contributing Guidelines
• I have checked that another pull request for this purpose does not exist
• I wrote some tests for this PR
• I have updated the relevant CHANGELOG
• I have created a PR for the documentation about this change

Small description of change:

changed how we compare strings in Confirmation validator

Thanks

[codecov]

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[niden]

Thank you @Izopi4a