docs: fix usage overview see-also links

[thehanslevi]

Addresses the broken-link portion of #8126.

What changed

• Updated the two outdated "See also" links in docs/source/learn/usage_overview.rst:
  • nb_tutorials/index.html -> :doc:Tutorials <learn/core_notebooks/index>``
  • nb_examples/index.html -> :doc:Examples nb:gallery``

Checks run

• rg -n "nb_tutorials/index.html|nb_examples/index.html" docs/source/learn/usage_overview.rst (before: both present)
• rg -n "nb_tutorials/index.html|nb_examples/index.html|Tutorials <learn/core_notebooks/index>|Examples <nb:gallery>" docs/source/learn/usage_overview.rst (after: only new targets present)
• Verified docs targets exist/referenced:
  • docs/source/learn/core_notebooks/index.md
  • docs/source/learn.md and docs/source/learn/core_notebooks/index.md reference nb:gallery
• Attempted docs linkcheck command from task plan:
  • make -C docs linkcheck (not available in this repo; no linkcheck make target)

Residual uncertainty

• I did not run a full docs build in this run; this PR keeps the change minimal and only updates two stale link targets.

[read-the-docs-community]

Documentation build overview

📚 pymc | 🛠️ Build #32818533 | 📁 Comparing a86b919 against latest (f09f6b6)

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5 files changed · ± 5 modified

± Modified

• glossary.html
• learn/usage_overview.html
• _modules/pytensor/tensor/basic.html
• _modules/pytensor/tensor/extra_ops.html
• _modules/pytensor/tensor/subtensor.html