fix(dspy): Loosen pydantic version

[isaacbmiller]

Loosen Pydantic version restriction to be >= 2.0

Reasoning is from #570

[isaacbmiller]

@thomasahle Would you anticipate any issues with this change?

[isaacbmiller]

I could also cap at 2.7

[paluchasz]

You could use pydantic="^2.0" which also ensures that it would be <3.0.0. See https://python-poetry.org/docs/dependency-specification/

[isaacbmiller]

Good call. Thanks!

[arnavsinghvi11]

@isaacbmiller this merged PR has errors with pyproject.toml. can you take a look and fix it?

Resolved https://github.com/stanfordnlp/dspy.git to commit d0e455a10797bef7e6793ae2fb64e0aa64555d12
  Installing build dependencies: started
  Installing build dependencies: finished with status 'done'
  Getting requirements to build wheel: started
  Getting requirements to build wheel: finished with status 'error'
  error: subprocess-exited-with-error
  
  × Getting requirements to build wheel did not run successfully.
  │ exit code: 1
  ╰─> [46 lines of output]
      configuration error: `project.dependencies[{data__dependencies_x}]` must be pep508
      DESCRIPTION:
          Project dependency specification according to PEP 508
      
      GIVEN VALUE:
          "pydantic=^2.0"
      
      OFFENDING RULE: 'format'
      
      DEFINITION:
          {
              "$id": "#/definitions/dependency",
              "title": "Dependency",
              "type": "string",
              "format": "pep508"
          }
      Traceback (most recent call last):
             ValueError: invalid pyproject.toml config: `project.dependencies[{data__dependencies_x}]`.
      configuration error: `project.dependencies[{data__dependencies_x}]` must be pep508
      [end of output]

[isaacbmiller]

Oops. Thanks for catching. will follow up soon