Cosmetic warning on import: TorchScript instance-level annotations

[chengjilai]

Importing mace.modules triggers a cosmetic warning:

UserWarning: The TorchScript type system doesn't support instance-level annotations on empty non-base types in `__init__`.

Root cause

Instance-level type annotations in GatedEquivariantBlock.__init__ (mace/modules/gate.py) are flagged by TorchScript. This is a known PyTorch issue (pytorch#89064, open since June 2024).

Fix

PR #1484 adds a warnings.filterwarnings in mace/modules/__init__.py to suppress the message. No functional impact — e3nn already does the same in its compile() path.