Accept PHP memory_limit of -1 as meeting requirement

[ghost]

A PHP memory_limit of '-1' is specified as 'unlimited'.

Before the change the checkmemory() function generates a Warning if the limit is set to -1. This shows up as a Warning in the Drupal Status Report, but more seriously also prevents the Drupal database update process (mydomain.com/update.php) from running.

After the change the value '-1' is accepted as meeting the requirement.

Overview

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Before

What is the old user-interface or technical-contract (as appropriate)?
For optimal clarity, include a concrete example such as a screenshot, GIF (LICEcap, SilentCast), or code-snippet.

After

What changed? What is new old user-interface or technical-contract?
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Technical Details

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Comments

Anything else you would like the reviewer to note

[civibot]

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[demeritcowboy]

xref: https://lab.civicrm.org/dev/core/-/issues/2289

• General standards
  • [r-explain] PASS
  • [r-user] PASS
  • [r-doc] PASS
  • [r-run] PASS
    • Works for both -1 and a typical value.
• Developer standards
  • [r-tech] PASS
  • [r-code] PASS
  • [r-maint] ____
  • [r-test] PASS