staticTargeting: add flag to switch default to true

[nathantournant]

What does this PR do?

• [ ] Adds new functionality
• [X] Alters existing functionality
• [ ] Fixes a bug
• [ ] Improves documentation or testing

Please briefly describe your changes as well as the motivation behind them:

• Now places the default value for staticTargeting to a flag in the controller's config map.

Code Quality Checklist

• [X] The documentation is up to date.
• [X] My code is sufficiently commented and passes continuous integration checks.
• [X] I have signed my commit (see Contributing Docs).

Testing

• [X] I leveraged continuous integration testing
  • [X] by depending on existing unit tests or end-to-end tests.
  • [ ] by adding new unit tests or end-to-end tests.
• [X] I manually tested the following steps:
  • Deploy the controller with the staticTargetingDefault field set to false, launch a disruption with staticTargeting unspecified, check out the description
  • Do all of those combinations (flag false/true, staticTargeting field unspecified/false/true) and assert you have the expected results.
  • [X] locally.
  • [ ] as a canary deployment to a cluster.