Improved handling of env reload request - handles older version of worker sdk

[kshyju]

Updating native placeholder to handle specialization request for function app payload which has older version worker package.

We will be updating the worker.sdk package to include a new property called "isSpecializable" canUsePlaceholder the "worker.config.json". The native placeholder will look for this property and if not present, it will the environment reload response with "failure" as status and a special exception. On the host we will check the exception associated with the failed env reload response and if it is this special exception. we will execute the fallback code - which is to shut down this channel and start a new channel with the customer payload dll.

For reference - the host changes are going to look like this: Azure/azure-functions-host#9602 - This is the host version I used to test my changes locally.

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• I have added all required tests (Unit tests, E2E tests)

Additional information

Additional PR information