fix: resolve CI/CD test failures and linting issues

tests/test_validators.py

@@ -1,7 +1,5 @@
 """Tests for syntax validation."""
 
-import pytest
-
 from config_convert.validators import validate
 
 
@@ -12,7 +10,7 @@ class TestValidateJSON:
         assert error is None
 
     def test_valid_json_pretty(self):
-        is_valid, error = validate('{\n  "name": "test\n"}', "json")
+        is_valid, error = validate('{\n  "name": "test"\n}', "json")
         assert is_valid is True
 
     def test_invalid_json(self):
@@ -35,7 +33,7 @@ class TestValidateYAML:
         data = """database:
   host: localhost
   port: 5432
- """
+"""
         is_valid, error = validate(data, "yaml")
         assert is_valid is True
 
@@ -53,9 +51,9 @@ class TestValidateTOML:
 
     def test_valid_toml_nested(self):
         data = """[database]
- host = "localhost"
- port = 5432
- """
+host = "localhost"
+port = 5432
+"""
         is_valid, error = validate(data, "toml")
         assert is_valid is True