Update gradle plugin, update gradle test plugin

OpenKeychain-Test/build.gradle

@@ -5,7 +5,7 @@ buildscript {
 
     dependencies {
         // NOTE: Always use fixed version codes not dynamic ones, e.g. 0.7.3 instead of 0.7.+, see README for more information
-        classpath 'com.novoda:gradle-android-test-plugin:0.10.1'
+        classpath 'com.novoda:gradle-android-test-plugin:0.10.4'
     }
 }