bpo-41690: Use a loop to collect args in the parser instead of recursion (GH-22053)

This program can segfault the parser by stack overflow:

```
import ast

code = "f(" + ",".join(['a' for _ in range(100000)]) + ")"
print("Ready!")
ast.parse(code)
```

the reason is that the rule for arguments has a simple recursion when collecting args:

args[expr_ty]:
    [...]
    | a=named_expression b=[',' c=args { c }] {
        [...] }
diff --git a/Parser/pegen.h b/Parser/pegen.h
index f407709..3e74e3a 100644
--- a/Parser/pegen.h
+++ b/Parser/pegen.h
@@ -257,6 +257,7 @@
 KeywordOrStarred *_PyPegen_keyword_or_starred(Parser *, void *, int);
 asdl_seq *_PyPegen_seq_extract_starred_exprs(Parser *, asdl_seq *);
 asdl_seq *_PyPegen_seq_delete_starred_exprs(Parser *, asdl_seq *);
+expr_ty _PyPegen_collect_call_seqs(Parser *, asdl_seq *, asdl_seq *);
 expr_ty _PyPegen_concatenate_strings(Parser *p, asdl_seq *);
 asdl_seq *_PyPegen_join_sequences(Parser *, asdl_seq *, asdl_seq *);
 int _PyPegen_check_barry_as_flufl(Parser *);