Restyle Reduce dangling session handle

[restyled-io]

A duplicate of #9225 with additional commits that automatically address
incorrect style, created by Restyled.

⚠️ Even though this PR is not a Fork, it contains outside contributions.
Please review accordingly.

Since the original Pull Request was opened as a fork in a contributor's
repository, we are unable to create a Pull Request branching from it with only
the style fixes.

The following Restylers made fixes:

• clang-format

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1. Merge this Pull Request instead of the original, or

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   the original Pull Request

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   ```console
   git remote add upstream https://github.com/project-chip/connectedhomeip.git
   git fetch upstream pull/<this PR number>/head
   git merge --ff-only FETCH_HEAD
   git push
   ```
   

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[todo]

currently SessionHandle is not able to identify a unauthenticated session, create an empty handle for it

connectedhomeip/src/transport/SessionHandle.h

Lines 65 to 73 in afc7ae0

	// TODO: currently SessionHandle is not able to identify a unauthenticated session, create an empty handle for it
	static SessionHandle TemporaryUnauthenticatedSession()
	{
	return SessionHandle(kPlaceholderNodeId, Transport::kUndefinedFabricIndex);
	}
	private:
	friend class SecureSessionMgr;
	NodeId mPeerNodeId;

---

This comment was generated by todo based on a TODO comment in afc7ae0 in #9234. cc @project-chip.