Support Long Timers for Out of Proc Languages ⏳📈🚀

[hossam-nasr]

This PR:

• Adds support for long timers for out-of-proc SDKs
• Adds a new schema version (to signify SDK support for long timers)
• Only allows OOProc to use the long timer API if using the new schema version

Issue describing the changes in this PR

Extension-side of resolving Azure/azure-functions-durable-js#325. JS SDK PR: Azure/azure-functions-durable-js#340

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation PR is ready to merge and referenced in pending_docs.md
• 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)
• My changes do not require any extra work to be leveraged by OutOfProc SDKs
  • Otherwise: That work is being tracked here: Support Long Timers azure-functions-durable-js#325
• My changes do not change the version of the WebJobs.Extensions.DurableTask package
  • Otherwise: major or minor version updates are reflected in /src/Worker.Extensions.DurableTask/AssemblyInfo.cs

[davidmrdavid]

It mostly looks good to me, but I left a few nits.
The only reason I'm not approving at this point is that AssemblyInfo change. What that change on purpose? If so, can you please explain it? Otherwise, I'd try removing it and making sure it all still works. Thanks!

[davidmrdavid]

Thank you for this work, our users will really appreciate this change. As always, squash and merge, then delete branch :)