chore: Update fakefs requirement from ~> 2.0.0 to ~> 2.2.0 (#970)

Updates the requirements on [fakefs](https://github.com/fakefs/fakefs) to permit the latest version.
- [Release notes](https://github.com/fakefs/fakefs/releases)
- [Changelog](https://github.com/fakefs/fakefs/blob/master/CHANGELOG.md)
- [Commits](fakefs/fakefs@v2.0.0...v2.2.0)

---
updated-dependencies:
- dependency-name: fakefs
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

appium_lib.gemspec

@@ -19,7 +19,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'tomlrb', '>= 1.1', '< 3.0'
 
   s.add_development_dependency 'appium_thor', '~> 1.1', '>= 1.1.4'
-  s.add_development_dependency 'fakefs', '~> 2.0.0'
+  s.add_development_dependency 'fakefs', '~> 2.2.0'
   s.add_development_dependency 'hashdiff', '~> 1.0.0'
   s.add_development_dependency 'posix-spawn', '~> 0.3'
   s.add_development_dependency 'pry'