fix: tls connections hanging when any connection does not complete handshake

[rohan-b99]

Ensures the main listener loop is not blocked when waiting for a TLS handshake to complete

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Checklist

Complete the checklist (and note appropriate exceptions) before the PR is marked ready-for-review.

• PR description explains the motivation for the change and relevant context for reviewing
• PR description links appropriate GitHub/Jira tickets (creating when necessary)
• Changeset is included for user-facing changes
• Changes are compatible¹
• Documentation² completed
• Performance impact assessed and acceptable
• Metrics and logs are added³ and documented
• Tests added and passing⁴
  • Unit tests
  • Integration tests
  • Manual tests, as necessary

To test:
Run the router with : cargo run -- -c apollo-router/tests/integration/fixtures/tls.router.yml -s examples/graphql/supergraph.graphql
In a new terminal, run: nc 127.0.0.1 <router-port>
In another terminal, run: curl -v -k https://127.0.0.1:<router-port>
The curl command should complete successfully

Exceptions

Note any exceptions here

Notes

Footnotes

1. It may be appropriate to bring upcoming changes to the attention of other (impacted) groups. Please endeavour to do this before seeking PR approval. The mechanism for doing this will vary considerably, so use your judgement as to how and when to do this. ↩

2. Configuration is an important part of many changes. Where applicable please try to document configuration examples. ↩

3. A lot of (if not most) features benefit from built-in observability and debug-level logs. Please read this guidance on metrics best-practices. ↩

4. Tick whichever testing boxes are applicable. If you are adding Manual Tests, please document the manual testing (extensively) in the Exceptions. ↩

[apollo-librarian]

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File Changes

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* graphos/routing/(latest)/configuration/yaml.mdx

Build ID: 996694ab363b207d17ed91bf
Build Logs: View logs

URL: https://www.apollographql.com/docs/deploy-preview/996694ab363b207d17ed91bf

[carodewig]

Looks great overall!

[carodewig]

LGTM! I'd suggest applying the AI style review bot's suggestions, but code changes look great