Description:
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When using mysqli_perpare/execute/bind/fetch combination to retrieve a MD5 hash from the database php replaces the last character of the hash throug a hex(00) character. A mysqli_query/fetch_row works correctly.

Reproduce code:
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$mysqli->prepare("SELECT MD5('a')");
$ps->execute();
$ps->bind_result($hash);
$ps->fetch();
$ps->close();

echo $hash;

Expected result:
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0cc175b9c0f1b6a831c399e269772661

Actual result:
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0cc175b9c0f1b6a831c399e26977266