[DX-278] Add new github team before renaming old one

[sebawo]

This pull request includes a small change to the CODEOWNERS file. The change updates the ownership assignment by adding the @smartcontractkit/devex-tooling team and includes a TODO comment to remove the @smartcontractkit/test-tooling-team after a GitHub team rename.

• CODEOWNERS: Added @smartcontractkit/devex-tooling team and included a TODO comment to remove @smartcontractkit/test-tooling-team after the GitHub team rename.

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Below is a summarization created by an LLM (gpt-4-0125-preview). Be mindful of hallucinations and verify accuracy.

Why

The change prepares for a GitHub team rename by adding a TODO comment and updating the CODEOWNERS file to include both the old and the new team names. This ensures continued access and oversight by the appropriate team during the transition period.

What

• CODEOWNERS
  • Added a TODO comment to remind to remove the old team name after the team rename on GitHub.
  • Updated the ownership line to include both @smartcontractkit/test-tooling-team and @smartcontractkit/devex-tooling, ensuring both teams are now listed as code owners.