undo redo minor refactor

[izulin]

Context

Refactored undo-redo code not to use big if-else statement.

How has this been tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature or improvement (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Additional language file or change to the existing one (translations)

Related issue(s):

Checklist:

• My code follows the code style of this project,
• My change requires a change to the documentation,
• I described the modification in the CHANGELOG.md file.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@e055cba). Click here to learn what that means.
The diff coverage is n/a.

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[wojciechczerniak]

LGTM