chore: update PHP and SimpleSAMLphp versions in Dockerfile

[dionisio-bot]

Backport of #36412

[changeset-bot]

⚠️ No Changeset found

Latest commit: 789f428

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[dionisio-bot]

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[github-actions]

PR Preview Action v1.6.2
🚀 View preview at https://RocketChat.github.io/Rocket.Chat/pr-preview/pr-36435/
Built to branch gh-pages at 2025-07-16 00:20 UTC. Preview will be ready when the GitHub Pages deployment is complete.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.55%. Comparing base (b7f4874) to head (789f428).
Report is 1 commits behind head on release-7.8.1.

Additional details and impacted files

@@                Coverage Diff                @@
##           release-7.8.1   #36435      +/-   ##
=================================================
+ Coverage          64.54%   64.55%   +0.01%     
=================================================
  Files               3147     3147              
  Lines             104632   104632              
  Branches           19765    19770       +5     
=================================================
+ Hits               67536    67548      +12     
+ Misses             34403    34395       -8     
+ Partials            2693     2689       -4     

Flag	Coverage Δ
unit	69.15% <ø> (+0.02%)	⬆️

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