Add WasbRemoteLogIO.from_config and register wasb remote logging scheme

[Andrushika]

Add WasbRemoteLogIO.from_config and register wasb remote logging scheme

What

Core resolves remote log handlers by URL scheme through ProvidersManager dispatch, added in #67056.This PR adds WasbRemoteLogIO.from_config() and registers the wasb scheme, so Azure Blob logging is built by the provider instead of the hardcoded branch in airflow_local_settings.py. Existing wasb:// configs resolve to an equivalent handler, and a from_config error falls back to the legacy path, so behaviour does not change.

Tested with a real task using remote_base_log_folder = wasb://logs against a local Azurite. The log uploaded to the airflow-logs container and read back. ProvidersManager().remote_logging_handler_by_scheme("wasb") returns WasbRemoteLogIO, so the resolver uses provider dispatch, not the legacy branch. Unit tests mirror TestS3RemoteLogIOFromConfig.

related: #70265
closes: #70268

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Generated-by: Claude Opus 4.8 following the guidelines

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[potiuk]

Faithful port. All four constructor arguments match the legacy wasb branch — base_log_folder, remote_base with the wasb:// prefix stripped, delete_local_copy, wasb_container — and applying | io_kwargs is right here, since wasb is one of the object-storage backends where legacy merges. (I reviewed this alongside the sibling ports; the two search backends deliberately do not merge, and #70295 currently gets that wrong.)

The io/fth split test is the one that earns its keep, and I checked it isn't passing vacuously:

("logging", "remote_task_handler_kwargs"): '{"delete_local_copy": true, "max_bytes": 1024}'
...
assert subject.delete_local_copy is True
assert not hasattr(subject, "max_bytes")

max_bytes is a real FileTaskHandler.__init__ parameter, so this exercises both sides with genuine names — the IO kwarg reaches the class, the file-handler kwarg is filtered. If the split logic broke, max_bytes would be forwarded and construction would raise, so the test guards the mechanism and not just the outcome.

One inherited oddity, not something to fix here: conf.get_mandatory_value(..., fallback="airflow-logs") is contradictory — mandatory with a fallback. It comes across verbatim from airflow_local_settings.py, so the port is accurate; worth someone untangling in core at some point.

Rebased onto main before merging.

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Drafted-by: Claude Code (Opus 5); reviewed by @potiuk before posting

[Andrushika]

Thanks for reviewing! The static check failure looks unrelated, could you please rerun it?