Bump cfgv from 3.2.0 to 3.4.0

Bumps [cfgv](https://github.com/asottile/cfgv) from 3.2.0 to 3.4.0.
- [Commits](asottile/cfgv@v3.2.0...v3.4.0)

---
updated-dependencies:
- dependency-name: cfgv
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

requirements-dev.txt

@@ -1,7 +1,7 @@
 attrs==21.4.0
 backports.entry-points-selectable==1.1.1
 certifi==2023.7.22
-cfgv==3.2.0
+cfgv==3.4.0
 charset-normalizer==2.0.7
 coverage==4.5.4
 distlib==0.3.7