Update action items

[RShaw026]

Description and Context

Earlier, the following warning was seen in the workflow: Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: actions/checkout@v2

This MR solves the issue by using actions/checkout@v3 instead of actions/checkout@v2.

Also, all the files are formatted using clang-format version 6.0 in this MR.

Related Issues and Pull Requests

• Closes #71
• Blocks
• Is blocked by
• Follows
• Precedes
• Related to
• Part of
• Composed of

How Has This Been Tested?

the workflow was manually run on this branch, and no warning was seen.

Checklist

• [x] My commit messages mention the appropriate GitHub issue numbers and are longer than one line where appropriate.
• [x] I have added/updated documentation where necessary.

Additional Information

Interested Parties / Possible Reviewers

@NoraHagmeyer @eulovi

[NoraHagmeyer]

@rshaw, can you open two MR for the two unrelated changes, please? I feel like going to a different version of clang format should be separate from changing the workflow. Especially since these changes warrant 2 different reviewers. Thanks!