Remove Int wrapper type from parser (#7577)

## Summary

This is only used for the `level` field in relative imports (e.g., `from
..foo import bar`). It seems unnecessary to use a wrapper here, so this
PR changes to a `u32` directly.

crates/ruff_python_parser/src/python.lalrpop

@@ -253,18 +253,18 @@ ImportStatement: ast::Stmt = {
     },
 };
 
-ImportFromLocation: (Option<ast::Int>, Option<ast::Identifier>) = {
+ImportFromLocation: (Option<u32>, Option<ast::Identifier>) = {
     <dots: ImportDots*> <name:DottedName> => {
-        (Some(ast::Int::new(dots.iter().map(ast::Int::to_u32).sum())), Some(name))
+        (Some(dots.iter().sum()), Some(name))
     },
     <dots: ImportDots+> => {
-        (Some(ast::Int::new(dots.iter().map(ast::Int::to_u32).sum())), None)
+        (Some(dots.iter().sum()), None)
     },
 };
 
-ImportDots: ast::Int = {
-    "..." => ast::Int::new(3),
-    "." => ast::Int::new(1),
+ImportDots: u32 = {
+    "..." => 3,
+    "." => 1,
 };
 
 ImportAsNames: Vec<ast::Alias> = {