Refactor and add integration tests (#150)

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## What was changed
- Refactored the integration tests present and added some more as well.
- The main refactoring was done in such a way that each type of test was
being tested against one of the three rollout strategies we have defined
for our controller.

## Why?
- More test coverage and also so that we can sleep better at night
knowing our controller is bullet proof

## Checklist
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1. Closes <!-- add issue number here -->

2. How was this tested:
- Tests

3. Any docs updates needed?
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      or point out where to update docs.temporal.io -->

Author: Shivs11