feat: added quickstart sample

[BigBlackWolf]

Description

Fixes #<ISSUE-NUMBER>

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Checklist

• [ ] I have followed Sample Guidelines from AUTHORING_GUIDE.MD
• [ ] README is updated to include all relevant information
• [ ] Tests pass: nox -s py-3.9 (see Test Environment Setup)
• [ ] Lint pass: nox -s lint (see Test Environment Setup)
• [ ] These samples need a new API enabled in testing projects to pass (let us know which ones)
• [ ] These samples need a new/updated env vars in testing projects set to pass (let us know which ones)
• [ ] This sample adds a new sample directory, and I updated the CODEOWNERS file with the codeowners for this sample
• [ ] This sample adds a new Product API, and I updated the Blunderbuss issue/PR auto-assigner with the codeowners for this sample
• [ ] Please merge this PR for me once it is approved

[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 1 region tag.

• iam/cloud-client/snippets/quickstart.py:16, tag iam_quickstart

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