Use the correct endpoint for MAXLOGAGE

[rdwebdesign]

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What does this PR aim to accomplish?:

Fix the response of api.php?getMaxlogage
The response for this call was always returning the default value (24), because it was not asking for the correct information.

How does this PR accomplish the above?:

The API call now receives the value of "maxlogage" from FTL, as expected.

What documentation changes (if any) are needed to support this PR?:

none.

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/pi-hole-ftl-v5-16-web-v5-13-and-core-v5-11-1-released/56384/1