`load_result` not working in batch jobs when using OIDC user

[soxofaan]

originally reported here https://discuss.eodc.eu/t/caching-openeo-results/197/22

using load_result fails with something like

 openeo_driver.errors.JobNotFoundException: The batch job ‘4cfc3e73-4847-483f-a580-34d765e86f30’ does not exist.

after some digging, I found that the job lookup inside a batch job does not work because the batch job uses the proxyuser as user id while the job registry uses (OIDC based) user id