XD-1914 Handle deploymentStatus for moduleCount zero

- If the module count for a module on a given stream is zero, then the stream is considered
deployed at least one module is deployed.
I see an issue with that approach as the `count.actual` is never incremented, hence (count.expected == 0 && count.actual > 0) is always false. and, in case of module count zero, even if we increment count.actual then, the moduleCount removal would only happen on a next iteration (if at least more than one container gets the module deployed). 

Is there any issue do you see with it is currently:
```
				if (count != null && (count.expected == 0 || ++count.actual == count.expected)) {
```
1. This will make sure the `moduleCount` map entry is removed as long as one **deployed** deployment status inside the loop. 
2. If the `moduleCount` map entry for the given key is removed, then if there are multiple matching containers then moduleCount map could return null. Hence, the `null` check.
3. In case of module count > 0, then `++count.actual` will make sure to handle it correctly.

On the TODO, what I meant was, once the moduleCount map for the given key is removed, we can possibly remove all the deployment statuses associated with that key. but I think that should be fine (given the null check we needed) except iterating over all the deploymentStatuses for the same key. If it is confusing, I can remove the TODO list.