Add X509 authentication tests.

[vbabanin]

JAVA-5866

[Copilot]

Pull Request Overview

This pull request adds comprehensive X.509 authentication tests for the MongoDB Java driver. The implementation introduces functional tests that validate X.509 certificate-based authentication across both synchronous and reactive drivers.

• Implements abstract test framework for X.509 authentication with parameterized SSL configurations
• Adds test implementations for both sync and reactive stream drivers
• Integrates X.509 authentication tests into the CI/CD pipeline with Evergreen configuration

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
AbstractX509AuthenticationTest.java	Core test logic with SSL context setup and parameterized test methods
X509AuthenticationTest.java (sync)	Sync driver implementation extending the abstract test class
X509AuthenticationTest.java (reactive)	Reactive streams implementation with sync adapter wrapper
run-x509-auth-tests.sh	Shell script for keystore provisioning and test execution
.evg.yml	Evergreen configuration additions for CI integration