Reduce use of deprecated typing aliases (#6358)

stubs/paramiko/paramiko/config.pyi

@@ -1,4 +1,4 @@
-from typing import IO, Any, Dict, Iterable, Pattern, Set
+from typing import IO, Any, Dict, Iterable, Pattern
 
 from paramiko.ssh_exception import ConfigParseError as ConfigParseError, CouldNotCanonicalize as CouldNotCanonicalize
 
@@ -17,7 +17,7 @@ class SSHConfig:
     def parse(self, file_obj: IO[str]) -> None: ...
     def lookup(self, hostname: str) -> SSHConfigDict: ...
     def canonicalize(self, hostname: str, options: SSHConfigDict, domains: Iterable[str]) -> str: ...
-    def get_hostnames(self) -> Set[str]: ...
+    def get_hostnames(self) -> set[str]: ...
 
 class LazyFqdn:
     fqdn: str | None