Fix for PHP 8.4

[remicollet]

php_mt_rand_range is available since 7.1

Using PHP_VERSION : 8.4.0alpha1

=====================================================================
TEST RESULT SUMMARY
---------------------------------------------------------------------
Exts skipped    :     0
Exts tested     :    17
---------------------------------------------------------------------

Number of tests :    10                10
Tests skipped   :     0 (  0.0%) --------
Tests warned    :     0 (  0.0%) (  0.0%)
Tests failed    :     0 (  0.0%) (  0.0%)
Tests passed    :    10 (100.0%) (100.0%)
---------------------------------------------------------------------
Time taken      : 12.363 seconds
=====================================================================

[wikimedia-helper-bot-for-github]

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