Update flake8-isort requirement from <4.3,>=4.0 to >=4.0,<5.1 in /requirements

[dependabot[bot]]

Updates the requirements on flake8-isort to permit the latest version.

Changelog

Sourced from flake8-isort's changelog.

5.0.0 (2022-10-08)

• Update dependencies. [gforcada]

• Revamp GitHub actions. [gforcada]

• Drop python 3.6, and add python 3.10. [gforcada]

• Use linters and formatters to keep code sane and beautiful. [gforcada]

4.2.0 (2022-08-04)

• Fix compatibility with flake8 version 5. [nhymxu]

4.1.2.post0 (2022-07-25)

• Release it as a wheel as well. [gforcada]

4.1.2 (2022-07-25)

• The package no longer depends on testfixtures.

4.1.1 (2021-10-14)

• Release py3 only wheels..

4.1.0 (2021-10-14)

• Support flake8 4.x [g-as]

• Switch from travis-ci to github actions. [g-as]

• Drop python 2.7 support and 3.5 as well [g-as]

4.0.0 (2020-08-11)

• Nothing changed yet.

... (truncated)

Commits

• cfc6c49 Preparing release 5.0.0
• 6eb4800 Merge pull request #117 from gforcada/overhaul
• 4114d4a Update CHANGES
• a498f9b cleanup
• c76bae4 cleanup the test file
• 41bf429 chore: run autoformatters (pyupgrade, isort, black)
• 4c57928 chore: rename tests file
• d56f00b fix(ci): fine tune the testing matrix
• 8bfa8b5 feat: overhaul testing
• 1c7dbc5 feat: pin dependencies
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot merge` will merge this PR after your CI passes on it - `@dependabot squash and merge` will squash and merge this PR after your CI passes on it - `@dependabot cancel merge` will cancel a previously requested merge and block automerging - `@dependabot reopen` will reopen this PR if it is closed - `@dependabot close` will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)