Issue 687 - fix for Coordinate in columnIndexFromString with new test cases

[yudina-m]

This is:

- [x] a bugfix
- [ ] a new feature

Checklist:

• Changes are covered by unit tests
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change
• Documentation is updated as necessary

Why this change is needed?

For the correct work of the \PhpOffice\PhpSpreadsheet\Cell\Coordinate::columnIndexFromString
Issue #687

[PowerKiKi]

Thanks for the contribution. Unfortunately I don't think it can be merged. First columnIndexFromString is very performance sensitive and extra validation via regexp is probably not a great idea performance wise. Second stripping the '$' in the reader seems a bit out of context.

Instead of those changes, I think \PhpOffice\PhpSpreadsheet\Cell\Coordinate::rangeBoundaries() only should be changed to strip '$' before using columnIndexFromString (and of courses unit tests should be adapted to reflect that)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
If this is still an issue for you, please try to help by debugging it further and sharing your results.
Thank you for your contributions.