Implement error handling for fit error metrics plots

[QuantumChemist]

With too little fit data, the following error occurs:

Traceback (most recent call last):                                                                                                            │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/jobflow_remote/jobs/run.py", line 49, in run_remote_job    │
│                  response = job.run(store=store)                                                                                                           │
│                             ^^^^^^^^^^^^^^^^^^^^                                                                                                           │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/jobflow/core/job.py", line 600, in run                     │
│                  response = function(*self.function_args, **self.function_kwargs)                                                                          │
│                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^                                                                          │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/autoplex/fitting/common/jobs.py", line 99, in              │
│              machine_learning_fit                                                                                                                          │
│                  train_test_error = gap_fitting(                                                                                                           │
│                                     ^^^^^^^^^^^^                                                                                                           │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/autoplex/fitting/common/utils.py", line 232, in            │
│              gap_fitting                                                                                                                                   │
│                  plot_energy_forces(                                                                                                                       │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/autoplex/data/common/utils.py", line 813, in               │
│              plot_energy_forces                                                                                                                            │
│                  energy_rmse_train = energy_plot(                                                                                                          │
│                                      ^^^^^^^^^^^^                                                                                                          │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/autoplex/data/common/utils.py", line 646, in energy_plot   │
│                  elim = (for_limits.min() - 0.01, for_limits.max() + 0.01)                                                                                 │
│                          ^^^^^^^^^^^^^^^^                                                                                                                  │
│                File "/user/miniconda3/envs/auto/lib/python3.11/site-packages/numpy/core/_methods.py", line 45, in _amin                 │
│                  return umr_minimum(a, axis, None, out, keepdims, initial, where)                                                                          │
│                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^                                                                          │
│              ValueError: zero-size array to reduction operation minimum which has no identity      

which only effects the GAP vs. DFT error metric plots.
The generated GAP potentials themselves looked fine in my test cases.
Therefore, I added a ValueError exception so that the workflow continues. The plots can be generated from GAP and QUIP data afterwards with the respective autoplex metrics functions if needed.

• replaced prints with logging
• one small edit to the README as part of the GitHub demo for @celinehalkali

[QuantumChemist]

@JaGeo , this PR would be ready for review and merging. 😃