Bump pyrsistent from 0.18.0 to 0.19.3

Bumps [pyrsistent](https://github.com/tobgu/pyrsistent) from 0.18.0 to 0.19.3.
- [Release notes](https://github.com/tobgu/pyrsistent/releases)
- [Changelog](https://github.com/tobgu/pyrsistent/blob/master/CHANGES.txt)
- [Commits](tobgu/pyrsistent@v0.18.0...v0.19.3)

---
updated-dependencies:
- dependency-name: pyrsistent
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>