Implement /security/thread_context_sharing endpoints for Go, Java and Python

[danielmercier]

Motivation

End to end test for trace correlation between tracers and agent.

Changes

Added the /security/thread_context_sharing endpoint for Python, Go, PHP and Java

[datadog-prod-us1-4]

🎉 All green!

❄️ No new flaky tests detected

_{This comment will be updated automatically if new data arrives.
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[github-actions]

CODEOWNERS have been resolved as:

utils/build/docker/php/weblogs/plain/security/thread_context_sharing.php  @DataDog/system-tests-reviewers
manifests/agent.yml                                                     @DataDog/system-tests-reviewers
manifests/golang.yml                                                    @DataDog/system-tests-reviewers
manifests/java.yml                                                      @DataDog/system-tests-reviewers
manifests/php.yml                                                       @DataDog/system-tests-reviewers
manifests/python.yml                                                    @DataDog/system-tests-reviewers
utils/_context/_scenarios/thread_context_sharing.py                     @DataDog/system-tests-core
utils/build/docker/agent/runtime-security.d/thread_context_sharing.policy  @DataDog/system-tests-reviewers
utils/build/docker/golang/app/net-http/main.go                          @DataDog/system-tests-reviewers
utils/build/docker/java/spring-boot/src/main/java/com/datadoghq/system_tests/springboot/App.java  @DataDog/system-tests-reviewers
utils/build/docker/php/apache-mod/php.conf                              @DataDog/system-tests-reviewers
utils/build/docker/php/php-fpm/php-fpm.conf                             @DataDog/system-tests-reviewers
utils/build/docker/python/flask/app.py                                  @DataDog/system-tests-reviewers