Update redirect-to-custom-domain.mdx

[seaneustace]

Wildcards are not supported in bulk redirects, this redirect will not work.

Summary

Screenshots (optional)

Documentation checklist

• The documentation style guide has been adhered to.
• If a larger change - such as adding a new page- an issue has been opened in relation to any incorrect or out of date information that this PR fixes.
• Files which have changed name or location have been allocated redirects.

[ToriLindsay]

@GregBrimble @WalshyDev Do you mind confirming this is correct?
Also that it's preferable to this PR #17562 which suggests the same thing, but instead suggests replacing * with rather than ? Thank you!

[GregBrimble]

This one looks good to me!

[ToriLindsay]

Thank you for your contribution @seaneustace !

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