Test cases in examples/ do not have time dependent solutions

[Keno]

The circuit examples in examples/ are static and do not exhibit time-dependent solutions. Ideally, future improvements to structural simplification would eliminate all equations in these models. Since they're used to test various structural simplification code, it would be good to change the examples to something e.g. with an opaque, time-varying voltage source that is not static.

[ValentinKaisermayer]

I think MTK already does that. And both examples in examples are ODEs and do have time dependent solutions. For instance, even though the input voltage is constant the voltage of the capacitor changes over time.

[ChrisRackauckas]

No, that's still an autonomous equation. The issue here is that we should have some non-autonomous equations in the tests.