[php8-compat][REF] Fix Date unit tests in php8 by passing in 00 inste…

[seamuslee001]

…ad of null for hours,minutes and seconds

Overview

This fixes a test failures such as

CRM_Utils_DateTest::testRelativeEarlierDay
Failed asserting that two arrays are equal.
--- Expected
+++ Actual
@@ @@
 Array (
     'from' => null
-    'to' => '20210605000000'
+    'to' => '20210605003229'
 )

Before

Date test fails in php8

After

Date tests pass in php8

Technical Details

as per https://www.php.net/manual/en/function.mktime.php#refsect1-function.mktime-changelog the hours, minutes and seconds is now nullable and this means that if null is passed in the current time values for that section is used

ping @eileenmcnaughton @totten @demeritcowboy

[civibot]

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[demeritcowboy]

Looks ok - just wondering what happens with month, day, year since it says they are also nullable now - I don't have php 8 installed anywhere but I suppose I should do that.