Remove failing assert

As of setuptools 77.0.3, this assert is no longer passing. This means
projects that require this for building cannot build, and projects that
use it at runtime (e.g. cothread's catools) cannot run.

It should be noted that this passes under setuptools 77.0.1, so there
is apparently a breaking change in a minor release.

Author: AlexanderWells-diamond

src/setuptools_dso/dsocmd.py

@@ -722,7 +722,6 @@ def run_command(self, cmd):
 # if right_before is specified build_dso is injected before that command
 # instead of as first dependency.
 def _needs_builddso(command, right_before=None):
-    assert issubclass(command, Command)
     # copy to avoid changing base class if sub_commands was just inherited
     _ = command.sub_commands[:]
     where = 0