fix: S3 endpoint environment variable name in local mode

[cuongvd23]

Issue #, if available:
#5262

Description of changes:
Change S3_ENDPOINT_URL_ENV_NAME from S3_ENDPOINT_URL to AWS_ENDPOINT_URL_S3

References:

• https://github.com/boto/botocore/blob/25cbbe2251d746b3f5ef0a4fcdb644def86937dc/botocore/configprovider.py#L1011

Merge Checklist

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• I have read the CONTRIBUTING doc
• I certify that the changes I am introducing will be backward compatible, and I have discussed concerns about this, if any, with the Python SDK team
• I used the commit message format described in CONTRIBUTING
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Tests

• I have added tests that prove my fix is effective or that my feature works (if appropriate)
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