Use of deprecated method for specification of types for JSONSchema

[max-moser]

Package version (if known): 1.4.0

Describe the bug

Invenio-Records uses a type-specification feature for JSONSchema validators which has been removed in version 4.0 of the jsonschema package.
This causes errors when trying to validate JSONSchemas with jsonschema>=4.0, e.g. in this PR for Invenio-OAIServer: inveniosoftware/invenio-oaiserver#203

Additional context

The offending line is in ext.py: https://github.com/inveniosoftware/invenio-records/blob/master/invenio_records/ext.py#L61

Related links in the jsonschema package:
Issue: python-jsonschema/jsonschema#681
Commit: python-jsonschema/jsonschema@d9f6384

Note: jsonschema has been pinned (>=3.0,<4) in some 1.5.0 pre-release, but the PR uses invenio-records 1.4.0.

[max-moser]

As mentioned in direct communication, we could create a new version (1.4.1) of invenio-records that does nothing except for pinning jsonschema to >=3,<4.
Since invenio-records 1.4.0 is obviously incompatible with jsonschema 4.x anyway, this shouldn't break anything but rather make problems more immediately obvious.

[max-moser]

Fixed in invenio-records 1.6.0, closing.