Fix pre-commit linter and release scripts

[vojtechjelinek]

Overview

1. This PR fixes Unable to run the cut_release_or_hotfix_branch script #15600 and fixes Unable to commit after #15557 got merged #15606
2. This PR does the following: Fixes more issues with importing typing_extensions

Essential Checklist

• The PR title starts with "Fix #bugnum: ", followed by a short, clear summary of the changes. (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
• The linter/Karma presubmit checks have passed locally on your machine.
• "Allow edits from maintainers" is checked. (See here for instructions on how to enable it.)
  • This lets reviewers restart your CircleCI tests for you.
• The PR is made from a branch that's not called "develop".

Proof that changes are correct

Proof of changes on desktop with slow/throttled network

Proof of changes on mobile phone

Proof of changes in Arabic language

PR Pointers

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[oppiabot]

Hi, @vojtechjelinek, this pull request does not have a "CHANGELOG: ..." label as mentioned in the PR pointers. Assigning @vojtechjelinek to add the required label. PRs without this label will not be merged. If you are unsure of which label to add, please ask the reviewers for guidance. Thanks!

[ankita240796]

LGTM for codeowner files, Thanks!