chore(deps): bump iso8601 from 1.1.0 to 2.0.0 (#503)

Bumps [iso8601](https://github.com/micktwomey/pyiso8601) from 1.1.0 to 2.0.0.
- [Release notes](https://github.com/micktwomey/pyiso8601/releases)
- [Changelog](https://github.com/micktwomey/pyiso8601/blob/main/CHANGELOG.md)
- [Commits](micktwomey/pyiso8601@1.1.0...2.0.0)

---
updated-dependencies:
- dependency-name: iso8601
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements-test.txt

@@ -1,4 +1,4 @@
-iso8601==1.1.0
+iso8601==2.0.0
 requests==2.31.0
 securesystemslib==0.28.0
 six==1.16.0