chore: Remove testcontainer example

[thomaspoignant]

Description

Remove testcontainer example

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (main@72eb917). Learn more about missing BASE report.
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2605   +/-   ##
=======================================
  Coverage        ?   85.48%           
=======================================
  Files           ?      100           
  Lines           ?     4444           
  Branches        ?        0           
=======================================
  Hits            ?     3799           
  Misses          ?      516           
  Partials        ?      129           

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