Bump gitaly-proto version to v0.39.0

Gemfile

@@ -398,7 +398,7 @@ group :ed25519 do
 end
 # Gitaly GRPC client
-gem 'gitaly-proto', '~> 0.38.0', require: 'gitaly'
+gem 'gitaly-proto', '~> 0.39.0', require: 'gitaly'
 gem 'toml-rb', '~> 0.3.15', require: false

Gemfile.lock

@@ -275,7 +275,7 @@ GEM
       po_to_json (>= 1.0.0)
       rails (>= 3.2.0)
     gherkin-ruby (0.3.2)
-    gitaly-proto (0.38.0)
+    gitaly-proto (0.39.0)
       google-protobuf (~> 3.1)
       grpc (~> 1.0)
     github-linguist (4.7.6)