Add support re.Pattern[str] to pattern field

[jag-k]

Change Summary

I think it just a simple idea about using already compiled regexp to set in pattern field.

Example:

import re

from pydantic import BaseModel, Field

TOKEN_RE = re.compile(r"glpat-.{20}")


class ModelWithToken(BaseModel):
    """Token model with secret."""

    token: SecretStr = Field(pattern=TOKEN_RE)  # Instead of `pattern=TOKEN_RE.pattern`

Related issue number

fix #9052

Checklist

• The pull request title is a good summary of the changes - it will be used in the changelog
• Unit tests for the changes exist
• Tests pass on CI
• Documentation reflects the changes where applicable — I don't think we need docs for this
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

Selected Reviewer: @davidhewitt

[codspeed-hq]

CodSpeed Performance Report

Merging #9053 will not alter performance

_{Comparing jag-k:feat-pattern-as-pattern (6e96b8d) with main (ac9e6ee)}

Summary

✅ 10 untouched benchmarks

[jag-k]

please review

[sydney-runkle]

Looks great, would be helpful to add some tests! Thanks!

[sydney-runkle]

@jag-k, ping!

[jag-k]

@jag-k, ping!

@sydney-runkle Sorry to keep you waiting. I missed your message a bit in the mail.

I added tests. Tell me, is everything okay with them?

[sydney-runkle]

Looks great, thanks for your work on this!