Fix error message mentioning wrong file

[jacklul]

While browsing through the code I noticed this:

// Add /etc/pihole/dhcp.lease to the ZIP archive if it exists
file_comment = "DHCP leases file";
file_path = "/etc/pihole/dhcp.leases";
if(file_exists(file_path) && !mz_zip_writer_add_file(zip, file_path+1, file_path, file_comment, (uint16_t)strlen(file_comment), MZ_BEST_COMPRESSION))
{
    mz_zip_writer_end(zip);
    return "Failed to add /etc/hosts to heap ZIP archive!"; // <--- definitely should not mention /etc/hosts here
}

This might lead to user confusion one day so it's better to correct it.

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What does this PR aim to accomplish?:

Corrects error message mentioning /etc/hosts instead of /etc/pihole/dhcp.leases in teleporter.c:184.

How does this PR accomplish the above?:

I edited it.

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[DL6ER]

Thank you!