[icat] read with timeout
Attributes like proposal, sample and dataset can be temporary unavailable for reading after changing state. This sometimes happens in CI: https://gitlab.esrf.fr/bliss/bliss/-/jobs/91912
I only managed to reproduce it locally by patching the ICAT server code so hard to make a test for this but manual testing with the patch shows the solution in the MR works.
Edited by Wout De Nolf