[Data] Remove ineffective retry code in plan_read_op

[bveeramani]

Why are these changes needed?

Currently, Ray Data calls read tasks with retries. The intended purpose is to retry transient errors while reading data.

ray/python/ray/data/_internal/planner/plan_read_op.py

Lines 103 to 109 in eda6d09

	yield from call_with_retry(
	f=read_task,
	description=f"read file {read_fn_name}",
	match=READ_FILE_RETRY_ON_ERRORS,
	max_attempts=READ_FILE_MAX_ATTEMPTS,
	max_backoff_s=READ_FILE_RETRY_MAX_BACKOFF_SECONDS,
	)

However, the code doesn't achieve the intended result because read tasks return generator objects, and Python will never raise runtime errors while returning a generator (Python might raise runtime errors when the programs iterates over the returned generator).

ray/python/ray/data/datasource/datasource.py

Lines 160 to 168 in eda6d09

	def __call__(self) -> Iterable[Block]:
	result = self._read_fn()
	if not hasattr(result, "__iter__"):
	DeprecationWarning(
	"Read function must return Iterable[Block], got {}. "
	"Probably you need to return `[block]` instead of "
	"`block`.".format(result)
	)
	yield from result

Related issue number

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    method in Tune, I've added it in doc/source/tune/api/ under the
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