Updating FunctionsNetHost (dotnet isolated worker) to 1.0.9

[kshyju]

Updating FunctionsNetHost (dotnet isolated worker) to 1.0.9. Azure/azure-functions-dotnet-worker#2552
Updated a test(which uses the actual worker configs) to reflect this change.

Pull request checklist

IMPORTANT: Currently, changes must be backported to the in-proc branch to be included in Core Tools and non-Flex deployments.

• Backporting to the in-proc branch is not required
  • Otherwise: Link to backporting PR - will follow
• 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
• My changes do not require diagnostic events changes
  • Otherwise: I have added/updated all related diagnostic events and their documentation (Documentation issue linked to PR)
• I have added all required tests (Unit tests, E2E tests)

Additional information

Additional PR information

[kshyju]

Many tests depend on the worker config provided by the referenced worker packages. The new DNI worker config requires a specific environment variable (WEBSITE_PLACEHOLDER_MODE) to be present. If this variable is absent, the worker will be skipped. Therefore, the tests need to include this environment variable. I am currently working on fixing them.

[kshyju]

The dotnet isolated worker config was updated to load only in placeholder mode. Few other tests, I was able to set the environment variable and that allows loading the dotnet isolated worker config. But for this test, there are other code path for which this test is running, where we return if we are in placeholder mode.

Considering the fact that, we are in the process of making this app setting a mandatory value, I think it may be okay to remove the "dotnet-isolated" case from this test.