Enable expected eslint strict rules

[rajsite]

🧹 Tech Debt

As part of the eslint 9 migration the strict typing rules were enabled by default in the styleguide.

This made us realize that several strict rules were not enabled in nimble yet when adopting eslint 9 and the rules were disabled in #2773. We should re-enable the rules and the violations.

[m-akinc]

I'm enabling two of the three for now. I'm leaving the third because it is not the right priority to fix right now. The third rule, @typescript-eslint/no-unnecessary-condition, has over 100 violations in nimble-components, mostly due to FAST and wafer-map APIs incorrectly declaring types as non-nullable, and our code correctly testing for null/undefined values.