tests: build error on 3.7,pypi,postgresql10,elasticsearch7

[ppanero]

The only packages diff compared to the 3.9 build are (not present or diff version)

3.7 (failing)

asttokens==2.0.5
executing==0.8.3
ipython==8.2.0
stack-data==0.2.0

3.9 (passing)

cached-property==1.5.2
ipython==7.32.0
typing_extensions==4.1.1

Failing exception is:

[180](https://github.com/inveniosoftware/invenio-drafts-resources/runs/5868837619?check_suite_focus=true#step:7:180)
        bucket = record.bucket
[181](https://github.com/inveniosoftware/invenio-drafts-resources/runs/5868837619?check_suite_focus=true#step:7:181)
>       size_limit = bucket.size_limit
[182](https://github.com/inveniosoftware/invenio-drafts-resources/runs/5868837619?check_suite_focus=true#step:7:182)
E       AttributeError: 'NoneType' object has no attribute 'size_limit'
[183](https://github.com/inveniosoftware/invenio-drafts-resources/runs/5868837619?check_suite_focus=true#step:7:183)

Note it does not always fail (e.g. cannot reproduce in local) so it seems to be a timing issue (e.g. something not commited fast enough, etc.)

[fenekku]

It fails on 3.9 too, so we can rule out Python version: https://github.com/inveniosoftware/invenio-drafts-resources/actions/runs/5463856950/jobs/9945084100 . Some concurrency/timing issue does seem the more likely problem.