Improve test coverage of Machine controller reconcileDelete

[sbueringer]

While adding sorting for hooks in condition messages it came up that we don't have test coverage for this part of the code: #11624 (comment)

The code we changed was adding sorting for hooks via these two PRs:

• 🌱 machine: sort list of hooks for stable condition messages #11487
• 🐛 Machine: sort list of pre-drain hooks for stable condition messages #11624

But the entire code for the pre-terminate and pre-drain hooks in reconcileDelete has no test coverage

[arshadd-b]

/assign

[arshadd-b]

I am interested and will work on it.

[sbueringer]

/triage accepted
/priority important-longterm