Automate documentation branch updates for releases

[rascani]

Summary

As part of the release process, all of the viable/strict branch references in documentation are updated to point at the new release branch. This was done manually for release/1.1 in #16722. This change automates this process by adding the replacement to the apply-release-changes.sh script.

Authored with Claude.

Test plan

./scripts/release/apply-release-changes.sh
# Manually verify that docs are updated with release branch.

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/17077

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

❌ 1 New Failure, 1 Unrelated Failure

As of commit bf0757d with merge base 11dc963 ():

NEW FAILURE - The following job has failed:

• pull / unittest-buck / linux / linux-job (gh)
  RuntimeError: Command docker exec -t c2ad5ba316d4934e9774105ef6ac5033e5ebc81791ecc95425a73786f56e7dbd /exec failed with exit code 3

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / unittest-buck / macos / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 3

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[github-actions]

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[mergennachin]

Thank you!