[tests] stop generating rspec temp file in current directory

[rogerluan]

Checklist

• I've run bundle exec rspec from the root directory to see all new and existing tests pass
• I've followed the fastlane code style and run bundle exec rubocop -a to ensure the code style is valid
• I see several green ci/circleci builds in the "All checks have passed" section of my PR (connect CircleCI to GitHub if not)
• I've updated the documentation if necessary.

Motivation and Context

Every time bundle exec rspec is run, this file was being created in the current dir:

This was bothering me, so this PR fixes just that 😄

Description

The file will be created in the temp dir instead, and thus will be deleted when the OS deems necessary.

Testing Steps

To test the file generation, run bundle exec rspec pilot/spec/test_exporter_spec.rb and/or bundle exec rspec pilot/spec/tester_importer_spec.rb in master.

To test this branch, modify your Gemfile as:

gem 'fastlane', git: 'https://github.com/fastlane/fastlane.git', branch: 'rogerluan-update-circleci'

And run bundle install to apply the changes.

Then run bundle exec rspec pilot/spec/test_exporter_spec.rb and/or bundle exec rspec pilot/spec/tester_importer_spec.rb again to verify that the file isn't being created in the current dir anymore.

[crazymanish]

💯

[AliSoftware]

❤️ This has bothered me for a while too, thanks for finally fixing it!