gh-62172: Document walktree() and getargs() in inspect

[sreehariannam]

Part of gh-62172 (documenting undocumented functions in the inspect module).

Continues the pattern from gh-153624 and gh-153628: documents walktree() and getargs(), which were previously missing from Doc/library/inspect.rst.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #33723747 | 📁 Comparing 303ac20 against main (7745710)

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1 file changed

± library/inspect.html

[picnixz]

You opened multiple PRs for documenting inspect. Can you just do it in one PR please?

[picnixz]

Please merge those changes in #153624