Use grpc 1.11.0

Gemfile

@@ -421,7 +421,7 @@ end
 
 # Gitaly GRPC client
 gem 'gitaly-proto', '~> 0.96.0', require: 'gitaly'
-gem 'grpc', '~> 1.10.0'
+gem 'grpc', '~> 1.11.0'
 
 # Locked until https://github.com/google/protobuf/issues/4210 is closed
 gem 'google-protobuf', '= 3.5.1'

Gemfile.lock

@@ -374,7 +374,7 @@ GEM
       rake
     grape_logging (1.7.0)
       grape
-    grpc (1.10.0)
+    grpc (1.11.0)
       google-protobuf (~> 3.1)
       googleapis-common-protos-types (~> 1.0.0)
       googleauth (>= 0.5.1, < 0.7)
@@ -1074,7 +1074,7 @@ DEPENDENCIES
   grape-entity (~> 0.6.0)
   grape-route-helpers (~> 2.1.0)
   grape_logging (~> 1.7)
-  grpc (~> 1.10.0)
+  grpc (~> 1.11.0)
   haml_lint (~> 0.26.0)
   hamlit (~> 2.6.1)
   hashie-forbidden_attributes