fix(fastfile): trim trailing whitespaces and correct typo

[JPedroAmorim]

What does this implement/fix? Explain your changes.

This is just a cleanup of some bad formatting and typos in the project's fastfile.

No functional changes were made.

Does this close any currently open issues?

No.

Any relevant logs, error output, etc?

None.

Any other comments?

There are some problems in this project Ruby and Fastlane setup.

• There's no uniform Ruby version used throughout the project. This might cause environment inconsistencies. I suggest doing is to create a .ruby-version file with a newer version and enforce a Ruby version management tool (e.g. RVM) to guarantee that every developer that runs the project is using the same version, as well as an up-to-date one.
• There are several linting/formatting issues in the project's fastfile. Traliling whitespace, inconsistent use of single and double quotes, inconsistent variable naming (some are snake cased and others are camel cased) are to name some. In this PR, I just fixed the most straightforward ones that don't enforce any specific linter/formatter. Although, I do suggest adopting a linter/formatter for your ruby files (e.g. Rubocop) and enforcing its use on pre-commit and pre-push hooks.

I can open issues for these points, if you want.

Where has this been tested?

As this is not iOS/Swift related, I've just ran the setup lane to guarantee that the fastfile properly compiles:

bundle exec fastlane setup

Fastlane version: fastlane (2.213.0) (Same as in Gemfile.lock)
Ruby Version: The oldest I could ran with: ruby 2.6.7p197 (2021-04-05 revision 67941)
MEGA Version: v10.3 (Latest)

Best regards, João Pedro de Amorim.