Delete .swift-version

[RomanPodymov]

Checklist

• [x] This is not a Apple's bug.
• [x] Reviewed the README and documents.
• [x] Searched existing issues for ensure not duplicated.

Expected Behavior

The .swift-version file is not in the project repository.

Current Behavior

The .swift-version file is in the project repository.

Detailed Description (Include Screenshots)

As I can guess the .swift-version file is using only by CocoaPods in this project. If so, the usage of this file is now deprecated.

Environments

• Library version: 1.2.0

• Swift version: 5.4

• iOS version: 14.5

• Xcode version: 12.5.1

• Devices/Simulators: iPod touch (7th generation) simulator

• CocoaPods/Carthage version: CocoaPods 1.10.1