fix: change schema coordinator error logs to warning

[jjaakola-aiven]

The logs changed are warnings, the coordinator should correct the issue.

About this change - What it does

References: #xxxxx

Why this way

[github-actions[bot]]

Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
karapace
utils.py
karapace/coordinator
schema_coordinator.py					280
karapace/protobuf
field_element.py
proto_file_element.py
proto_normalizations.py
schema.py
Project Total

This report was generated by python-coverage-comment-action