support rdkit 2026.03.4

We see the following failures on equality checks when using rdkit 2026.

My naive guess is that it's due to changes in what attributes are included in rdkit representation:

https://github.com/rdkit/rdkit/releases#release-Release_2026_03_4

related to https://github.com/OpenFreeEnergy/openfe/issues/2067

FAILED src/openfe/tests/protocols/openmm_rfe/test_hybrid_top_protocol.py::test_setup_dry_sim_default_vacuum[repex] - assert <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33d372510> == <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33ef88c30>
 +  where <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33ef88c30> = <openfe.protocols.openmm_rfe._rfe_utils.relative.HybridTopologyFactory object at 0x309a2fcb0>.hybrid_topology
FAILED src/openfe/tests/protocols/openmm_rfe/test_hybrid_top_protocol.py::test_setup_dry_sim_default_vacuum[sams] - assert <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x13b7c8c00> == <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33d502e50>
 +  where <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33d502e50> = <openfe.protocols.openmm_rfe._rfe_utils.relative.HybridTopologyFactory object at 0x33fb24050>.hybrid_topology
FAILED src/openfe/tests/protocols/openmm_rfe/test_hybrid_top_protocol.py::test_setup_dry_sim_default_vacuum[independent] - assert <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33f13d2b0> == <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33d267110>
 +  where <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33d267110> = <openfe.protocols.openmm_rfe._rfe_utils.relative.HybridTopologyFactory object at 0x33fb24f50>.hybrid_topology
FAILED src/openfe/tests/protocols/openmm_rfe/test_hybrid_top_protocol.py::test_setup_dry_sim_default_vacuum[InDePeNdENT] - assert <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33f1cd7b0> == <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33f8f2060>
 +  where <mdtraj.Topology with 1 chains, 1 residues, 16 atoms, 16 bonds at 0x33f8f2060> = <openfe.protocols.openmm_rfe._rfe_utils.relative.HybridTopologyFactory object at 0x348528e10>.hybrid_topology