Run the initial request with a nonpositive retry timeout

[zhechen-cs]

Description

Always run the initial request in MinimalRetry and Retry, including when the timeout is zero or negative. Previously these values skipped the request and raised an unrelated TypeError from raise None.

If the request fails after the deadline, propagate its exception without sleeping. Regression tests cover both retry classes, successful results, retryable connection and rate-limit errors, and non-retryable errors.

Fixes #2198

Status

Ready for review.

Validation

• Common, connection, utility and HTTP tests: 213 passed, 1 skipped, 16 subtests passed (Python 3.12; NO_INTERNET=1, loopback proxy bypass).
• New regressions fail on the unmodified production code.
• Black, isort, flake8, pylint and git diff --check pass for the changed files.
• The full provider matrix and live cloud integration tests were not run.

Checklist

• Code linting
• Documentation (no public API change)
• Tests
• ICLA (small bug fix)