fix typing issue

[vishalvvr]

Error:

s3_resource: boto3.resource, bucket_name: str, file_paths: str | List
TypeError: unsupported operand type(s) for |: 'type' and '_SpecialGenericAlias'

How to reproduce

Run function delete_files from opl/s3_tools.py script with python3.9

Fix:

Use typing.Union instead of | because | is not supported in python versions < 3.10

ref: https://docs.python.org/3/library/typing.html#typing.Union

Syntax	Python 3.9 and below	Python 3.10+	Python 3.12+
Union[str, List[str]]	✅ Supported	✅ Supported	✅ Supported
`str	list[str]`	❌ Not supported	✅ Supported

[jhutar]

Thank you!