Websockets: fix passing log group ARN

[christophgysin]

The log group ARN contains a trailing ":*" that seems to cause
deployment to fail. Instead, generate the ARN with the trailing
wildcard.

What did you implement:

Closes #6304

How did you implement it:

Construct the log group ARN using Fn::Sub.

How can we verify it:

See issue referenced above.

Todos:

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• Update the messages below

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

[pmuens]

Hey @christophgysin thanks for working on this. I tried to reproduce this bug running our latest v1.46.0 version. (Un)fortunately I was not able to reproduce it.

Is there any additional service info you can provide (aside from that written down in the issue description) so that we can test it on our end?

Thanks in advance.

---

Edit:

Here's the serverless.yml I've used:

service: test

provider:
  name: aws
  runtime: nodejs10.x
  logs:
    websocket: true

functions:
  test:
    handler: handler.hello
    events:
      - websocket: $connect

[christophgysin]

@pmuens I can reproduce it also with v1.46.0. It seems that it only fails if you try to enable the logs on a service that is already deployed.

Can you try to disable the logs, deploy, enable them, and deploy again?

[pmuens]

Thanks for following-up @christophgysin 👍

I was able to reproduce the issue and can confirm that your PR fixes the issue. LGTM