API-Key: Use strict_encode64 to avoid adding new lines to result

Author: picandocodigo

elasticsearch-transport/lib/elasticsearch/transport/client.rb

@@ -244,7 +244,7 @@ def __auto_detect_adapter
       # Credentials is the base64 encoding of id and api_key joined by a colon
       # @see https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-create-api-key.html
       def __encode(api_key)
-        Base64.encode64([api_key[:id], api_key[:api_key]].join(':'))
+        Base64.strict_encode64([api_key[:id], api_key[:api_key]].join(':'))
       end
     end
   end

elasticsearch-transport/spec/elasticsearch/transport/client_spec.rb

@@ -63,7 +63,7 @@
     it 'Adds the ApiKey header to the connection' do
       expect(
         client.transport.connections.first.connection.headers['Authorization']
-      ).to eq("ApiKey #{Base64.encode64('my_id:my_api_key')}")
+      ).to eq("ApiKey #{Base64.strict_encode64('my_id:my_api_key')}")
     end
   end