py-pip_audit: update to 2.6.0.

## [2.6.0]

### Added

* Added option to skip dependency resolution via `pip` with the `--disable-pip`
  flag. This option can only be used with hashed requirements files or when the
  `--no-deps` flag has been provided
  ([#610](https://github.com/pypa/pip-audit/pull/610))

(wiz)