Python dependency: Bump fixtures from 4.0.1 to 4.1.0 in /web/regression (#6410)

Bumps [fixtures](https://github.com/testing-cabal/fixtures) from 4.0.1 to 4.1.0.
- [Changelog](https://github.com/testing-cabal/fixtures/blob/master/NEWS)
- [Commits](testing-cabal/fixtures@4.0.1...4.1.0)

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

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

Author: dependabot[bot]

web/regression/requirements.txt

@@ -17,7 +17,7 @@
 # Add all the development dependencies here
 ###########################################
 extras==1.0.0
-fixtures==4.0.1
+fixtures==4.1.0
 linecache2==1.0.0
 pbr==5.11.1
 pycodestyle>=2.5.0