Update php Docker tag to v8.4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
php	stage	minor	8.2-alpine -> 8.4-alpine

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.92%. Comparing base (4212011) to head (f48f26f).
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Additional details and impacted files

@@            Coverage Diff            @@
##               main      #25   +/-   ##
=========================================
  Coverage     83.92%   83.92%           
  Complexity      388      388           
=========================================
  Files            25       25           
  Lines           927      927           
=========================================
  Hits            778      778           
  Misses          149      149           

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