release_v2 requires python >= 3.10

The readme states (in both main and release_v2) that python 3.8+ is compatible but with python < 3.10, submitting training jobs in the release_v2 branch fails with:

```
Traceback (most recent call last):
File "/Users/njourdan/workspace/cli_test/.venv/bin/hyperpod", line 3, in
from hyperpod_cli.cli import cli
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/cli.py", line 20, in
from hyperpod_cli.commands.job import (
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/commands/job.py", line 90, in
from hyperpod_cli.validators.job_validator import (
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/validators/job_validator.py", line 36, in
from hyperpod_cli.validators.recipe_models import HfRecipeSchema, NovaRecipeSchema, NeuronHfRecipeSchema, NovaEvaluationRecipeSchema
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/validators/recipe_models/__init__.py", line 1, in
from hyperpod_cli.validators.recipe_models.hf.model import HfRecipeSchema
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/validators/recipe_models/hf/model.py", line 15, in
class TrainerConfig(BaseModel):
File "/Users/njourdan/workspace/cli_test/sagemaker-hyperpod-cli/src/hyperpod_cli/validators/recipe_models/hf/model.py", line 18, in TrainerConfig
devices: Optional[int|str] = None
TypeError: unsupported operand type(s) for |: 'type' and 'type'
```

This must be stated in the readme to avoid confusion and delays. The error is non-descriptive regarding python version compatibility.