Fix typo in dns option descriptions

[rrobgill]

What does this PR aim to accomplish?:

Fix typo in descriptions of dns.specialDomains.mozillaCanary and dns.specialDomains.iCloudPrivateRelay

Reported at https://discourse.pi-hole.net/t/typos-in-menu-settings/76935

How does this PR accomplish the above?:

Deleting the word replies and substituting reply.

Tests updated to reflect this change.

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