Added example code for s3 - getting a PDF from an S3 bucket and saving it

[7empestx]

aws-doc-sdk-examples Pull Request

Thank you for making a submission to the aws-doc-sdk-examples repository. For more information about submitting pull requests to this repository, see Guidelines for contributing.

NOTE: This pull request (PR) template contains two sections. Use the section that applies to your submission, and remove the section which doesn't apply.

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I'm submitting a new SDK code example

Confirm you have met the following minimum requirements:

• Add the following copyright notice to the top of each file. See the LICENSE agreement for the terms of the copyright.

Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0

• Create unit tests for all paths through the code, and confirm that the all the tests pass. For recommendations, see How we test code examples.
• Run a linter against all code and implement the resulting suggestions. For recommendations, see Linters run on check in.
• Add minimum usage documentation as comments in the code. For recommendations, see Code comment guidelines.

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I'm resolving an issue with an existing code example

Describe the changes you have made here, including any issue numbers.

Confirm you have met the following minimum requirements:

• Test the changed code. For recommendations, see How we test code examples.
• Run a linter against the changed code and implement the resulting suggestions. For recommendations, see Linters run on check in.

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Open source license adherence

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.