Verifying that the metadata that were sent to the ERMDS are effectively the ones you get when calling the get on the same SWHID.

Implementation wise, this reading step is currently done in the deposit test [1] but not in the runtime code [2].
The idea would be to add that reading step in the runtime code.

[1] https://forge.softwareheritage.org/source/swh-deposit/browse/master/swh/deposit/tests/api/test_deposit_update.py$666-669
[2] https://forge.softwareheritage.org/source/swh-deposit/browse/master/swh/deposit/api/deposit_update.py$264-278