Extensions loaded by the gateway classloader do not work with AT-TLS

Describe the bug
When running Zowe v3.3.0+ with AT-TLS, the apiml-sample-extension's /api/v1/greeting endpoint is not reachable. This sample extension is loaded through the ZWE_GATEWAY_SHARED_LIBS environment variable.

When issuing a request against /api/v1/greeting, the gateway responds with ZWEAO404E: The service can not find the requested resource.. When issuing the request through the /gateway/api/v1/greeting endpoint, the gateway responds with a TLS Error, ZWEAM511E (and a dump of a plaintext html page w/ HTTP 400 - Bad Request).

Steps to Reproduce

1. Run Zowe 3.3.0 or later with both AT-TLS and theapiml-sample-extension enabled.
2. Try accessing the /api/v1/greeting endpoint or the gateway-routed version.

Expected behavior
Both URLs should return Hello, I'm a sample extension!

Logs
The server logs indicated no match was found for the api/v1/greeting endpoint.

Details

• Version and build number: 3.3.14-SNAPSHOT build # 1357
• Test environment: Marist 9, 10, 11

REST API client (in case of REST API issue):

• Technology: Chrome, Bruno, curl
• OS: MacOS Sequoia

Reproduce the failure with Zowe 3.3.0 or later, AT-TLS, and the apiml-sample-extension loaded through ZWE_GATEWAY_SHARED_LIBS. Start by tracing gateway classloader loading and routing for /api/v1/greeting and /gateway/api/v1/greeting; done means both URLs return "Hello, I'm a sample extension!" without the 404 or TLS error.