[ruff] Fix false positive for t-strings in default-factory-kwarg (RUF026) (#20032)

Closes #19993

## Summary
Recognize t strings as never being callable to avoid false positives on
RUF026.

crates/ruff_linter/resources/test/fixtures/ruff/RUF026.py

@@ -118,3 +118,10 @@ def func():
         return lambda: value
 
     defaultdict(constant_factory("<missing>"))
+
+def func():
+    defaultdict(default_factory=t"")  # OK
+
+
+def func():
+    defaultdict(default_factory=t"hello")  # OK

crates/ruff_linter/src/rules/ruff/rules/default_factory_kwarg.rs

@@ -123,7 +123,8 @@ fn is_non_callable_value(value: &Expr) -> bool {
             | Expr::SetComp(_)
             | Expr::DictComp(_)
             | Expr::Generator(_)
-            | Expr::FString(_))
+            | Expr::FString(_)
+            | Expr::TString(_))
 }
 
 /// Generate an [`Expr`] to replace `defaultdict(default_factory=callable)` with