V2 webhook updates

[keithmacaulay]

• Bumping benchling-sdk to v1.13.0 for updated webhook models
• Updating handler.py to use V2 webhooks ahead of V0 deprecation (https://docs.benchling.com/changelog/explicit-webhook-subscriptions-and-webhook-version-update)

[rweinberger]

Code changes look great, tested it locally and works fine! Just one more thing to add into this PR: we'll soon be releasing the ability to explicitly subscribe to specific webhooks via the manifest. In order to be forwards-compatible with that world, we should augment the manifest.yaml file with the following subscriptions section that includes the two webhooks that this app needs in order to function properly:

subscriptions:
  deliveryMethod: WEBHOOK
  messages:
  - type: v2.canvas.initialized
  - type: v2.canvas.userInteracted

For now, we're still sending all webhooks to existing apps, but we won't be doing that forever. So if we don't make this manifest change to opt in to receiving these webhooks, future example apps created from the manifest will actually no longer receive these webhooks.

[rweinberger]

ship it!! 🚢 🚢 and thank you so much for taking the initiative to put this PR up 🎉