add pydantic 2 to requirements

[vicilliar]

• Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes/features)
• Docs have been added / updated (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
  requirements update

• What is the current behavior? (You can also link to an open issue here)
  no

• What is the new behavior (if this is a feature change)?
  pydantic 2 is in requirements (needed for tests)

• Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)
  no

• Other information: