Bumped podspec version to 3.0

Author: j-sid

GTXiLib.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "GTXiLib"
-  s.version      = "2.1"
+  s.version      = "3.0"
   s.summary      = "iOS Accessibility testing library."
   s.description  = <<-DESC
   iOS Accessibility testing library that works with XCTest based frameworks.
@@ -9,6 +9,6 @@ Pod::Spec.new do |s|
   s.license      = "Apache License 2.0"
   s.author       = "j-sid"
   s.platform     = :ios
-  s.source       = { :git => "https://github.com/google/GTXiLib.git", :tag => "2.1.0" }
+  s.source       = { :git => "https://github.com/google/GTXiLib.git", :tag => "3.0.0" }
   s.source_files = "Classes/**/*.{h,m,swift}"
 end