plot_tree fails with ValueError Invalid RGBA argument

### Describe the bug

When using `plot_tree` with `filled=True` (so the nodes are colored), one sometimes gets a `ValueError` such as
```
Invalid RGBA argument: '#cb 3-8d'
```

The same `plot_tree` will work fine if `filled=False`, and draw a decision tree. Below is an example. I attach two files with the dump of the DecisionTree and the list of columns used.

Thank you.

### Steps/Code to Reproduce

```
# BUG: fails with ValueError: Invalid RGBA argument: '#cb 4-8c'
import joblib
from sklearn.tree import plot_tree

dt = joblib.load('_br.dmp')
cols = joblib.load('_cols.dmp')
plot_tree(dt,
          feature_names=cols,
          class_names=['Reject', 'Accept'],
          filled=True, rounded=True,
          impurity=True,
          label='root',
          )
```


[_br.dmp](https://github.com/user-attachments/files/16512624/_br.dmp)
[_cols.dmp](https://github.com/user-attachments/files/16512625/_cols.dmp)


### Expected Results

No ValueError should be thrown and the plot should be drawn and correctly colored.

### Actual Results

ValueError Invalid RGBA argument: '#cb 3-8d'

### Versions

```shell
System:
    python: 3.11.4 (main, Jun  7 2023, 12:45:48) [GCC 11.3.0]
executable: /mnt/c/Workspace/py-pip-workspaces/pert.ai.main/.venv/bin/python
   machine: Linux-5.15.153.1-microsoft-standard-WSL2-x86_64-with-glibc2.35

Python dependencies:
      sklearn: 1.5.1
          pip: 24.2
   setuptools: 65.5.0
        numpy: 1.26.4
        scipy: 1.12.0
       Cython: None
       pandas: 2.2.2
   matplotlib: 3.9.1
       joblib: 1.3.2
threadpoolctl: 3.3.0

Built with OpenMP: True

threadpoolctl info:
       user_api: blas
   internal_api: openblas
    num_threads: 8
         prefix: libopenblas
       filepath: /mnt/c/Workspace/py-pip-workspaces/pert.ai.main/.venv/lib/python3.11/site-packages/numpy.libs/libopenblas64_p-r0-0cf96a72.3.23.dev.so
        version: 0.3.23.dev
threading_layer: pthreads
   architecture: SkylakeX

       user_api: blas
   internal_api: openblas
    num_threads: 8
         prefix: libopenblas
       filepath: /mnt/c/Workspace/py-pip-workspaces/pert.ai.main/.venv/lib/python3.11/site-packages/scipy.libs/libopenblasp-r0-23e5df77.3.21.dev.so
        version: 0.3.21.dev
threading_layer: pthreads
   architecture: SkylakeX

       user_api: openmp
   internal_api: openmp
    num_threads: 8
         prefix: libgomp
       filepath: /mnt/c/Workspace/py-pip-workspaces/pert.ai.main/.venv/lib/python3.11/site-packages/scikit_learn.libs/libgomp-a34b3233.so.1.0.0
        version: None
```

COMMENT:
@Siddharth-Latthe-07 thank you for the effort. I tried both of your suggestions and they're both broken, the first has the same exception
'''
ValueError: Invalid RGBA argument: '#cb 3-8d'
'''

while the second suggestion breaks with the exception
'''
TypeError: got an unexpected keyword argument 'colors'
'''

The Decision Tree classifier works, you have its pickle file included in the problem description above.
Matplotlib and scikit-learn versions are indeed the latest, as mentioned above.
I'd appreciate any other ideas. Thanks.

Labels: Bug, Needs Triage