Description:
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getmxrr() always returns true on alpine linux.

Recently the following bug was fixed https://bugs.php.net/bug.php?id=78008 thanks to this PR: https://github.com/php/php-src/pull/5854 and it was merged into the 7.4.9 release.

Our A, CNAME and MX record tests were failing before we upgraded to 7.4.9 today and now A and CNAME tests do pass correctly (they use checkdnsrr()), however MX test doesn't.

Test script:
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var_dump(getmxrr('meta.stackoverflow.com', $hosts));

Expected result:
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bool(false)

Actual result:
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bool(true)