[flake8-comprehensions] Handle template strings for comprehension fixes (#18710)

Essentially this PR ensures that when we do fixes like this:

```diff
- t"{set(f(x) for x in foo)}"
+ t"{ {f(x) for x in foo} }"
```
we are correctly adding whitespace around the braces. 

This logic is already in place for f-strings and just needed to be
generalized to interpolated strings.

crates/ruff_python_semantic/src/model.rs

@@ -1944,6 +1944,11 @@ impl<'a> SemanticModel<'a> {
         self.flags.intersects(SemanticModelFlags::T_STRING)
     }
 
+    /// Return `true` if the model is in an f-string or t-string.
+    pub const fn in_interpolated_string(&self) -> bool {
+        self.in_f_string() || self.in_t_string()
+    }
+
     /// Return `true` if the model is in an f-string replacement field.
     pub const fn in_interpolated_string_replacement_field(&self) -> bool {
         self.flags