Merge bitcoin/bitcoin#28009: script, test: python typing and linter updates

6c97757a48 script: appease spelling linter (Jon Atack)
1316119ce7 script: update ignored-words.txt (Jon Atack)
146c861da2 script: update linter dependencies (Jon Atack)
92408224a4 test: fix PEP484 no implicit optional argument types errors (Jon Atack)
f86a301433 script, test: add missing python type annotations (Jon Atack)

Pull request description:

  With these updates, `./test/lint/lint-python.py` and `./test/lint/lint-spelling.py` should be green again for developers using relatively recent Python dependencies, in particular mypy 0.991 (released 11/2022) and later. Please see the commit messages for details.

ACKs for top commit:
  fanquake:
    ACK 6c97757a48

Tree-SHA512: 8a46a4d36d5978affdcecf4f2ace20ca1b52d483e098304911a2169afe60ccb9b042fa90c04b762d94f3ce53d2cafe6f24476ae839867a770c7f31e7e7242d99

test/functional/test_framework/coverage.py

@@ -11,6 +11,7 @@ testing.
 import os
 
 from .authproxy import AuthServiceProxy
+from typing import Optional
 
 REFERENCE_FILENAME = 'rpc_interface.txt'
 
@@ -20,7 +21,7 @@ class AuthServiceProxyWrapper():
     An object that wraps AuthServiceProxy to record specific RPC calls.
 
     """
-    def __init__(self, auth_service_proxy_instance: AuthServiceProxy, rpc_url: str, coverage_logfile: str=None):
+    def __init__(self, auth_service_proxy_instance: AuthServiceProxy, rpc_url: str, coverage_logfile: Optional[str]=None):
         """
         Kwargs:
             auth_service_proxy_instance: the instance being wrapped.

test/functional/test_framework/test_framework.py

@@ -92,7 +92,7 @@ class BitcoinTestFramework(metaclass=BitcoinTestMetaClass):
 
     This class also contains various public and private helper methods."""
 
-    def __init__(self):
+    def __init__(self) -> None:
         """Sets test framework defaults. Do not override this method. Instead, override the set_test_params() method"""
         self.chain: str = 'regtest'
         self.setup_clean_chain: bool = False

test/functional/test_framework/util.py

@@ -309,7 +309,7 @@ class PortSeed:
     n = None
 
 
-def get_rpc_proxy(url: str, node_number: int, *, timeout: int=None, coveragedir: str=None) -> coverage.AuthServiceProxyWrapper:
+def get_rpc_proxy(url: str, node_number: int, *, timeout: Optional[int]=None, coveragedir: Optional[str]=None) -> coverage.AuthServiceProxyWrapper:
     """
     Args:
         url: URL of the RPC server to call