Coding Standards: Clarify time units for various timeout or expiration values.

This changeset implements a clearer and more consistent timeout/duration/expiration format. It updates time durations used in various files, as per WordPress coding standards:

- If the value can be represented as an integer (not a fractional) number of minutes (hours, etc.), use the appropriate constant (e.g.: `MINUTE_IN_SECONDS`) multiplied by that number.
- Otherwise, keep the value as is and add a comment with the units for clarity.

Follow-up to [11823], [13177], [21996], [37747], [53714].

Props hztyfoon, audrasjb, arrasel403, krupalpanchal, GaryJ, SergeyBiryukov, peterwilsoncc, rudlinkon, costdev, robinwpdeveloper.
Fixes #56293.
See #55647.


git-svn-id: https://develop.svn.wordpress.org/trunk@54113 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/class-wp-debug-data.php

@@ -1597,7 +1597,7 @@ class WP_Debug_Data {
 		// The max_execution_time defaults to 0 when PHP runs from cli.
 		// We still want to limit it below.
 		if ( empty( $max_execution_time ) ) {
-			$max_execution_time = 30;
+			$max_execution_time = 30; // 30 seconds.
 		}
 
 		if ( $max_execution_time > 20 ) {