fix broken pre-commit hooks by upgrading isort

[cj81499]

PR Checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature (please, look at the "Scope of the project" section in the README.md file)
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

Issue Number: N/A

pre-commit fails to install isort

What is the new behavior?

pre-commit succesfully installs isort

Does this PR introduce a breaking change?

• Yes
• No

Other information

Relates to #1067

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[f0rmiga]

@cj81499 Could you sign the CLA, please?

[cj81499]

Working on it! I'm making changes on behalf of my company (Ocient) and I have a meeting scheduled with my manager (about getting it signed) later today.