Hearbeat reporting

[madebyrogal]

MOD extend bots and sinks with errorMsg

Description

Changes proposed in this pull request:

• Extend heart beat by adding health status report

Testing

• This PR needs to be tested with the PR https://github.com/kubeshop/botkube-cloud/pull/1189, where you can find how to test e2e flow

Related issue(s)

https://github.com/kubeshop/botkube-cloud/issues/142
https://github.com/kubeshop/botkube-cloud/pull/1189

[mszostok]

Tested e2e, works as expected 👌

But let's agree on code changes before merging 🙂

[mszostok]

1. it doesn't make sens to have a global var here. Let's move it to the healtChecker that is responsible for it
2. no need to repeat the interfaces (HealthNotifierSink/HealthNotifierBot). You should have a single interface in place which expect it (healthChecker)
3. if / else statement is repeated, while it's common for all integrations, please see linked code changes to see how it can be changed.
4. FailedSink and FailedBot, referring to the same. The healthChecker - it doesn't care, just have single one.
5. You don't need to be worried about integration name, you can use it on 'nil'

    func Test(t *testing.T) {
       app, err := NewSocketSlackDemo()
       assert.Error(t, err)
       
       fmt.Println(app.IntegrationName())
    }
    
    func NewSocketSlackDemo() (*SocketSlack, error) {
       return nil, errors.New("fake")
    }

Changes in code based on feedback above: c472d4d