Create a new boto3 session per thread

[karan6181]

Description of changes:

• Create a new boto3 session for every new thread. Session objects are not thread safe and should not be shared across threads and processes. Creating a new Session object for each thread or process.
• It is recommended to create a resource instance for each thread / process in a multithreaded or multiprocess application rather than sharing a single instance among the threads / processes.

Issue #, if available:

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