## Summary
A minor quality-of-life improvement: add
[`#[track_caller]`](https://doc.rust-lang.org/reference/attributes/codegen.html#the-track_caller-attribute)
attribute to `Type::expect_xyz()` methods and some `TypeInference` methods such that the panic-location
is reported one level higher up in the stack trace.
before: reports location inside the `Type::expect_class_literal()`
method. Not very useful.
```
thread 'types::infer::tests::deferred_annotation_builtin' panicked at crates/red_knot_python_semantic/src/types.rs:304:14:
Expected a Type::ClassLiteral variant
```
after: reports location at the `Type::expect_class_literal()` call site,
where the error was made.
```
thread 'types::infer::tests::deferred_annotation_builtin' panicked at crates/red_knot_python_semantic/src/types/infer.rs:4302:14:
Expected a Type::ClassLiteral variant
```
## Test Plan
Called `expect_class_literal()` on something that's not a
`Type::ClassLiteral` and saw that the error was reported at the call
site.