feat: relax selenium webdriver version (#357)

Author: KazuCocoa

appium_lib_core.gemspec

@@ -22,7 +22,7 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ['lib']
 
-  spec.add_runtime_dependency 'selenium-webdriver', '~> 4.0.0'
+  spec.add_runtime_dependency 'selenium-webdriver', '~> 4.0'
   spec.add_runtime_dependency 'faye-websocket', '~> 0.11.0'
 
   spec.add_development_dependency 'rake', '~> 13.0'