--rmlmapper argument isn't respected

[rmeissn]

Expected behaviour:
Running /bin/cli.js --rmlmapper /rmlmapper.jar boots up a working version of the service

Observed behaviour:

info:    No path to an RMLMapper jar is defined.
(node:71) UnhandledPromiseRejectionWarning: ReferenceError: LatestTagNameOrVersion is not defined
    at downloadWrapper (/rmlmapper-webapi-js/lib/download-rmlmapper.js:27:50)
    at runMicrotasks (<anonymous>)
    at processTicksAndRejections (internal/process/task_queues.js:95:5)
    at async start (/rmlmapper-webapi-js/bin/cli.js:98:42)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:71) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:71) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Changing the path to e.g. / or /rmlmapper won't work either

Environment:
Container Environment
Distro: node:lts-alpine or node:14-alpine
Installed all necessary packages (curl python3 openjdk17-jre git)
Downloaded rmlmapper-jar manually by wget https://github.com/RMLio/rmlmapper-java/releases/download/v6.1.2/rmlmapper-6.1.2-r366-all.jar -O /rmlmapper.jar