refactor: change typing annotations in tests folder (#3594)

* refactor(log_router.py): change variable type annotation from List to list for better consistency
refactor(utils.py): change variable type annotation from Dict to dict for better consistency
refactor(base.py): change variable type annotation from Optional to Union for better clarity
refactor(callback.py): change variable type annotation from Dict to dict for better consistency
refactor(chat.py): change variable type annotation from Optional to Union for better clarity
refactor(endpoints.py): change variable type annotation from Optional to Union for better clarity
refactor(flows.py): change variable type annotation from List to list for better consistency

refactor(api): update response_model annotations to use lowercase list for consistency and improve readability

refactor(store.py): update type annotations for query parameters in get_components endpoint to improve code readability and maintainability
feat(store.py): add support for type hinting Union and list types in query parameters for better data validation and documentation

* run make format

* refactor(input_mixin.py): update typing annotations for variables to use union types for better clarity and compatibility with Python 3.10
refactor(inputs.py): update typing annotations for variables to use union types and import necessary modules for compatibility with Python 3.10

* refactor(base.py): remove unnecessary imports and update typing for fields in Input and Output classes
feat(base.py): add support for specifying field types more explicitly in Input and Output classes
feat(frontend_node/base.py): enhance typing and field definitions in FrontendNode class
feat(frontend_node/custom_components.py): improve typing and field definitions in CustomComponentFrontendNode and ComponentFrontendNode classes
feat(template/base.py): update typing for fields in Template class and remove unnecessary imports

* refactor(inputs): remove unnecessary Optional import from typing in input_mixin.py and inputs.py files to improve code readability and maintainability

* refactor(schema.py): change 'Type' to 'type' for consistency in type annotations
refactor(schema.py): change 'list' to 'List' and 'Literal' to 'literal' for correct type hinting in create_input_schema function

* refactor(utils.py): change typing annotations from List and Union to list and type to follow PEP 585 standards
refactor(test_schema.py): change typing annotations from List and List to list and list to follow PEP 585 standards
refactor(test_graph.py): change typing annotations from Type and Union to type and Vertex | None to follow PEP 585 standards
refactor(test_io_schema.py): change typing annotations from List and List to list and list to follow PEP 585 standards
refactor(test_custom_component.py): update file reading method to remove unnecessary "r" mode
refactor(test_helper_components.py): update file reading method to remove unnecessary "r" mode
refactor(test_kubernetes_secrets.py): update b64encode method argument to bytes type
refactor(test_template.py): change typing annotations from Optional, List, and Dict to list, dict, and None to follow PEP 585 standards

* [autofix.ci] apply automated fixes

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

src/backend/tests/unit/graph/test_graph.py

@@ -1,7 +1,6 @@
 import copy
 import json
 import pickle
-from typing import Type, Union
 
 import pytest
 
@@ -62,7 +61,7 @@ def sample_nodes():
     ]
 
 
-def get_node_by_type(graph, node_type: Type[Vertex]) -> Union[Vertex, None]:
+def get_node_by_type(graph, node_type: type[Vertex]) -> Vertex | None:
     """Get a node by type"""
     return next((node for node in graph.vertices if isinstance(node, node_type)), None)