Core: fix some memory leak sources without removing caching (#2400)

* Core: fix some memory leak sources

* Core: run gc before detecting memory leaks

* Core: restore caching in BaseClasses.MultiWorld

* SM: move spheres cache to MultiWorld._sm_spheres to avoid memory leak

* Test: add tests for world memory leaks

* Test: limit WorldTestBase leak-check to py>=3.11

---------

Co-authored-by: Fabian Dill <fabian.dill@web.de>

Utils.py

@@ -74,6 +74,8 @@ def snes_to_pc(value: int) -> int:
 
 
 RetType = typing.TypeVar("RetType")
+S = typing.TypeVar("S")
+T = typing.TypeVar("T")
 
 
 def cache_argsless(function: typing.Callable[[], RetType]) -> typing.Callable[[], RetType]:
@@ -91,6 +93,31 @@ def cache_argsless(function: typing.Callable[[], RetType]) -> typing.Callable[[]
     return _wrap
 
 
+def cache_self1(function: typing.Callable[[S, T], RetType]) -> typing.Callable[[S, T], RetType]:
+    """Specialized cache for self + 1 arg. Does not keep global ref to self and skips building a dict key tuple."""
+
+    assert function.__code__.co_argcount == 2, "Can only cache 2 argument functions with this cache."
+
+    cache_name = f"__cache_{function.__name__}__"
+
+    @functools.wraps(function)
+    def wrap(self: S, arg: T) -> RetType:
+        cache: Optional[Dict[T, RetType]] = typing.cast(Optional[Dict[T, RetType]],
+                                                        getattr(self, cache_name, None))
+        if cache is None:
+            res = function(self, arg)
+            setattr(self, cache_name, {arg: res})
+            return res
+        try:
+            return cache[arg]
+        except KeyError:
+            res = function(self, arg)
+            cache[arg] = res
+            return res
+
+    return wrap
+
+
 def is_frozen() -> bool:
     return typing.cast(bool, getattr(sys, 'frozen', False))