Pre and post deployment lifecycle hooks

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**Description**
This gives customers the ability to run validation checks (health checks, smoke tests) in a function's deployment lifecycle, particularly before code/after code/configuration updates, thus providing safe deployment controls for customers. Please leave a comment so that we can reach out to you to get additional feedback.

**Additional context**
1) How do you typically roll out your changes in Lambda functions? (All-at-once, canary, blue-green)

2) How would you use lifecycle hooks in your deployment process?

3) What pre-deployment validation checks do you perform before deploying your function?

4) What post-deployment validation checks do you perform before deploying your function? (Health checks, custom validation scripts)