Fix: Cocoapods doesn’t like dirs that start with ./

I wasted a huge amount of time debugging this madness.

examples/objective-c/auth_sample/AuthTestService.podspec

@@ -17,7 +17,7 @@ Pod::Spec.new do |s|
   s.dependency "!ProtoCompiler-gRPCPlugin", "~> 0.14"
 
   # Pods directory corresponding to this app's Podfile, relative to the location of this podspec.
-  pods_root = './Pods'
+  pods_root = 'Pods'
 
   # Path where Cocoapods downloads protoc and the gRPC plugin.
   protoc_dir = "#{pods_root}/!ProtoCompiler"

examples/objective-c/helloworld/HelloWorld.podspec

@@ -17,7 +17,7 @@ Pod::Spec.new do |s|
   s.dependency "!ProtoCompiler-gRPCPlugin", "~> 0.14"
 
   # Pods directory corresponding to this app's Podfile, relative to the location of this podspec.
-  pods_root = './Pods'
+  pods_root = 'Pods'
 
   # Path where Cocoapods downloads protoc and the gRPC plugin.
   protoc_dir = "#{pods_root}/!ProtoCompiler"

examples/objective-c/route_guide/RouteGuide.podspec

@@ -17,7 +17,7 @@ Pod::Spec.new do |s|
   s.dependency "!ProtoCompiler-gRPCPlugin", "~> 0.14"
 
   # Pods directory corresponding to this app's Podfile, relative to the location of this podspec.
-  pods_root = './Pods'
+  pods_root = 'Pods'
 
   # Path where Cocoapods downloads protoc and the gRPC plugin.
   protoc_dir = "#{pods_root}/!ProtoCompiler"