Lots of "No authorization token was found" in conan-proxy during probably Builder time

```
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: UnauthorizedError: No authorization token was found
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at middleware (/home/ubuntu/ceconan/conanproxy/node_modules/express-jwt/lib/index.js:79:
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at /home/ubuntu/ceconan/conanproxy/node_modules/express-unless/index.js:47:5
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at Layer.handle [as handle_request] (/home/ubuntu/ceconan/conanproxy/node_modules/expres
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at trim_prefix (/home/ubuntu/ceconan/conanproxy/node_modules/express/lib/router/index.js
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at /home/ubuntu/ceconan/conanproxy/node_modules/express/lib/router/index.js:284:7
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at Function.process_params (/home/ubuntu/ceconan/conanproxy/node_modules/express/lib/rou
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at next (/home/ubuntu/ceconan/conanproxy/node_modules/express/lib/router/index.js:275:10
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at urlencodedParser (/home/ubuntu/ceconan/conanproxy/node_modules/body-parser/lib/types/
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at Layer.handle [as handle_request] (/home/ubuntu/ceconan/conanproxy/node_modules/expres
Nov 08 01:00:47 ip-172-30-0-161 ce-conan[2034]: at trim_prefix (/home/ubuntu/ceconan/conanproxy/node_modules/express/lib/router/index.js
```

A couple of calls require authentication (sending build logs on failure, setting a buildstatus as fixed and setting build annotations) - the library builder Should be logging in, getting the JWT Token and transmitting it along with the requests.

Something appears to be not working here / broken.

Start by tracing the conan-proxy authentication middleware and the library builder's login and request flow, using the express-jwt stack trace as the entry point. Reproduce the failures during Builder activity and verify that authenticated calls for build logs, fixed status, and annotations carry a JWT without producing authorization errors.

Written by the indexing model from the issue text.