Add __all__ (#13704)

stubs/boltons/@tests/stubtest_allowlist.txt

@@ -1,19 +1,2 @@
-# TODO: missing from stub
-boltons.debugutils.__all__
-boltons.dictutils.__all__
-boltons.excutils.__all__
-boltons.fileutils.__all__
-boltons.formatutils.__all__
-boltons.gcutils.__all__
-boltons.jsonutils.__all__
-boltons.listutils.__all__
-boltons.namedutils.__all__
-boltons.pathutils.__all__
-boltons.queueutils.__all__
-boltons.setutils.__all__
-boltons.strutils.__all__
-boltons.tableutils.__all__
-boltons.tbutils.__all__
-
 boltons.funcutils.CachedInstancePartial.__partialmethod__
 boltons.funcutils.InstancePartial.__partialmethod__