fix: stop tracking Swift package manager xcworkspace

[landonr]

Fixes #91

RxOptional-SPM.xcodeproj should be generated by CI only and not tracked in the repo.

In order for Carthage to successfully build this project there can't be any xcodeproj's without a project.pbxproj file. The parent RxOptional-SPM.xcodeproj is in the .gitignore however the contents.xcworkspacedata is tracked in this repository so the xcodeproj is still being included.

[freak4pc]

Good fix, but CI is failing, can you fix it?
Thanks

[landonr]

Good fix, but CI is failing, can you fix it?
Thanks

These failures don't seem specific to my changes so I'm not sure what to do.

• Lint, build and test / build is failing with a 403 forbidden when its trying to post a comment
• ci/circleCI: Build Error seems like it has only succeeded once since it was integrated into the project

[ashfurrow]

I don't even see a Circle config yml file in the repo, and it's failing on master. Let's merge 👍

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[ashfurrow]

@landonr thank you for the contribution! If you're looking for another contribution to make, there's #93 🙃 But no pressure!