fix: Python 3.8 AST compatibility and ruff formatting

- Add deprecated AST node types (Index, Num, Str, Bytes, NameConstant)
  to the safe eval allowlist for Python 3.8 compatibility
- Fix ruff format in test_issues.py

Author: sean2077

jsonpath/jsonpath.py

@@ -165,6 +165,8 @@ class JSONPath:
             # Context
             ast.Load,
         }
+        # Python 3.8 compatibility: deprecated AST nodes removed in 3.12
+        | {getattr(ast, n) for n in ("Index", "Num", "Str", "Bytes", "NameConstant") if hasattr(ast, n)}
     )
     _ALLOWED_NAMES = frozenset({"__obj", "len", "RegexPattern"})
     _ALLOWED_CALLS = frozenset({"len", "RegexPattern"})

tests/test_issues.py

@@ -93,9 +93,7 @@ def test_bare_at_numeric_comparison(self):
     def test_bare_at_regex(self):
         """Bare @ should work with regex matching."""
         data = {"tags": ["web", "owasp:software_and_data_integrity_failures"]}
-        assert JSONPath("$.tags[?(@ =~ /owasp:.+/)]").parse(data) == [
-            "owasp:software_and_data_integrity_failures"
-        ]
+        assert JSONPath("$.tags[?(@ =~ /owasp:.+/)]").parse(data) == ["owasp:software_and_data_integrity_failures"]
 
     def test_bare_at_in_operator(self):
         """Bare @ with 'in' operator."""