feat: add suport for node16 runtime

[lcsales98]

What did you implement:

Closes #631

It will become available to use the nodejs16 runtime.

How did you implement it:

I'm updated the available runtimes at src/config/runtime.ts.

How can we verify it:

Can you generate an azure function with serverless-framework and deploy it with nodejs16 runtime.
Ex: runtime: nodejs16

Todos:

Note: Run npm run test:ci to run all validation checks on proposed changes

• Ensure there are no lint errors.
  Validate via npm run lint
  Note: Some reported issues can be automatically fixed by running npm run lint:fix
• Write tests and confirm existing functionality is not broken.
  Validate via npm test
• Write documentation
• Provide verification config / commands / resources
• Enable "Allow edits from maintainers" for this PR
• Update the messages below

Is this ready for review?: YES
Is it a breaking change?: NO

[medikoo]

Thank you @lcsales98! Please see my comments

[danielwaghorn]

Are there any updates on being able to get this merged at all? Happy to help if required.

[medikoo]

Are there any updates on being able to get this merged at all? Happy to help if required.

The only problem was that author of PR didn't mark this PR as ready for re-review. Anyway it looks as good to take

[medikoo]

I've merged it, yet it doesn't seem to be validated in CI, and locally for me tests fails.

Before releasing it, it'll be good to fix the CI in this project (I've created an issue: #645) and ensure that locally all tests passes