[pylint] Fix docs example that produced different output (PLW0603) (#18216)

Author: twentyone212121

crates/ruff_linter/src/rules/pylint/rules/global_statement.rs

@@ -31,8 +31,9 @@ use crate::checkers::ast::Checker;
 ///
 ///
 /// def foo():
+///     var = 10
 ///     print(var)
-///     return 10
+///     return var
 ///
 ///
 /// var = foo()