OptimizableBatch and stress relaxations

[lbluque]

Add functionality to include cell relaxations in structural relaxations for models that implement stress prediction. This PR also enables batch calculations with ASE optimizers.

• [X] Extends the OCPCalculator to enable stress predictions, and relaxations with ASE filters.
• [x] Extends core.common.relaxation.ml_relax to enable batch relaxations including stress.
• [x] Includes a new class OptimizableBatch that can be used with ASE optimizers or with the existing LBFGS implementation
• [x] Includes a UnitCellOptimizableBatch to allow batch stress relaxations
• ~Includes a ExpCellOptimizableBatch to allow batch stress relaxations~ will do this in a separate PR

TODO

• [x] Unit tests (missing tests with unit cell relaxation, pending models that can predict stress)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 63.97695% with 125 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...m/core/common/relaxation/optimizers/optimizable.py	56.11%	104 Missing :warning:
...c/fairchem/core/common/relaxation/ml_relaxation.py	11.76%	15 Missing :warning:
src/fairchem/core/common/relaxation/ase_utils.py	85.18%	4 Missing :warning:
...m/core/common/relaxation/optimizers/lbfgs_torch.py	98.11%	1 Missing :warning:
src/fairchem/core/datasets/ase_datasets.py	50.00%	1 Missing :warning:

Files with missing lines	Coverage Δ
src/fairchem/core/common/relaxation/__init__.py	100.00% <100.00%> (ø)
...chem/core/common/relaxation/optimizers/__init__.py	100.00% <100.00%> (ø)
src/fairchem/core/models/base.py	88.40% <100.00%> (-0.09%)	:arrow_down:
src/fairchem/core/trainers/base_trainer.py	86.12% <ø> (ø)
src/fairchem/core/trainers/ocp_trainer.py	69.49% <100.00%> (ø)
...m/core/common/relaxation/optimizers/lbfgs_torch.py	98.11% <98.11%> (+82.35%)	:arrow_up:
src/fairchem/core/datasets/ase_datasets.py	87.09% <50.00%> (+0.27%)	:arrow_up:
src/fairchem/core/common/relaxation/ase_utils.py	81.30% <85.18%> (+19.35%)	:arrow_up:
...c/fairchem/core/common/relaxation/ml_relaxation.py	24.44% <11.76%> (-3.34%)	:arrow_down:
...m/core/common/relaxation/optimizers/optimizable.py	56.11% <56.11%> (ø)