Bump pygraphviz from 1.13 to 1.14 (#100)

Bumps [pygraphviz](https://github.com/pygraphviz/pygraphviz) from 1.13 to 1.14.
- [Release notes](https://github.com/pygraphviz/pygraphviz/releases)
- [Changelog](https://github.com/pygraphviz/pygraphviz/blob/main/RELEASE.rst)
- [Commits](pygraphviz/pygraphviz@pygraphviz-1.13...pygraphviz-1.14)

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

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

Author: dependabot[bot]

requirements.txt

@@ -1,3 +1,3 @@
 puremagic==1.27
-pygraphviz==1.13
+pygraphviz==1.14
 svg.path==6.3