Fixed Proxy cert broken URL (Azure#26725)

Author: Nivedit Jain

doc/dev/test_proxy_migration_guide.md

@@ -433,7 +433,7 @@ For more details on proxy startup, please refer to the [proxy documentation][det
 
 [pipelines_ci]: https://github.com/Azure/azure-sdk-for-python/blob/5ba894966ed6b0e1ee8d854871f8c2da36a73d79/sdk/eventgrid/ci.yml#L30
 [pipelines_live]: https://github.com/Azure/azure-sdk-for-python/blob/e2b5852deaef04752c1323d2ab0958f83b98858f/sdk/textanalytics/tests.yml#L26-L27
-[proxy_cert_docs]: https://github.com/Azure/azure-sdk-tools/blob/main/tools/test-proxy/documentation/trusting-cert-per-language.md
+[proxy_cert_docs]: https://github.com/Azure/azure-sdk-tools/blob/main/tools/test-proxy/documentation/test-proxy/trusting-cert-per-language.md
 [py_sanitizers]: https://github.com/Azure/azure-sdk-for-python/blob/main/tools/azure-sdk-tools/devtools_testutils/sanitizers.py
 [pytest_collection]: https://docs.pytest.org/latest/goodpractices.html#test-discovery
 [pytest_fixtures]: https://docs.pytest.org/latest/fixture.html#scope-sharing-fixtures-across-classes-modules-packages-or-session