Remove CallArguments abstraction (#6279)

## Summary

This PR removes a now-unnecessary abstraction from `helper.rs`
(`CallArguments`), in favor of adding methods to `Arguments` directly,
which helps with discoverability.

crates/ruff_python_semantic/src/analyze/logging.rs

@@ -1,7 +1,6 @@
-use ruff_python_ast::{self as ast, Expr, Keyword};
-
 use ruff_python_ast::call_path::{collect_call_path, from_qualified_name};
-use ruff_python_ast::helpers::{find_keyword, is_const_true};
+use ruff_python_ast::helpers::is_const_true;
+use ruff_python_ast::{self as ast, Arguments, Expr, Keyword};
 
 use crate::model::SemanticModel;
 
@@ -61,8 +60,8 @@ pub fn is_logger_candidate(
 
 /// If the keywords to a  logging call contain `exc_info=True` or `exc_info=sys.exc_info()`,
 /// return the `Keyword` for `exc_info`.
-pub fn exc_info<'a>(keywords: &'a [Keyword], semantic: &SemanticModel) -> Option<&'a Keyword> {
-    let exc_info = find_keyword(keywords, "exc_info")?;
+pub fn exc_info<'a>(arguments: &'a Arguments, semantic: &SemanticModel) -> Option<&'a Keyword> {
+    let exc_info = arguments.find_keyword("exc_info")?;
 
     // Ex) `logging.error("...", exc_info=True)`
     if is_const_true(&exc_info.value) {