fix(permissionsBoundary): apply permissionsBoundary

[DubKF]

This PR allows using a Permissions Boundary defined in the provider level e.g.

provider:
  name: aws
  runtime: python3.9
  # the permisions boundary goes here 
  rolePermissionsBoundary: arn:aws:iam::[account]:policy/permission_boundary  
  # ...

Previously, the boundary was only applied to the created lambda execution role, but was missing on the created roles for functions of the state machine as described in issue 395 some time ago.

We run into the same issue yesterday well using the newest version of serverless and this plugin. The submitted fix worked for us.

[DubKF]

@lopburny Could you perhaps have a look and provide some guidance or workflow approval as I'm a 1st time contributor ;)

[lopburny]

Hi @DubKF Thanks for this PR. Looks good to me.

[lopburny]

🎉 This PR is included in version 3.12.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[nabsource]

please add this option to the docs/readme