chore(dependencies): externalize versions to properties (#443)

updates kork to 5.3.4
updates fiat to 1.0.4
updates spinnaker-gradle-project to 6.5.0

build.gradle

@@ -15,19 +15,15 @@
  */
 
 buildscript {
-    ext {
-      korkVersion = "5.2.0"
-      fiatVersion = "1.0.0"
-    }
     repositories {
         jcenter()
         maven { url "https://spinnaker.bintray.com/gradle" }
         maven { url "https://plugins.gradle.org/m2/" }
     }
     dependencies {
-        classpath 'com.netflix.spinnaker.gradle:spinnaker-dev-plugin:6.3.0'
+        classpath "com.netflix.spinnaker.gradle:spinnaker-dev-plugin:$spinnakerGradleVersion"
         if (Boolean.valueOf(enablePublishing)) {
-          classpath 'com.netflix.spinnaker.gradle:spinnaker-gradle-project:6.3.0'
+          classpath "com.netflix.spinnaker.gradle:spinnaker-gradle-project:$spinnakerGradleVersion"
         }
     }
 }

gradle.properties

@@ -1,2 +1,5 @@
 org.gradle.parallel=true
 enablePublishing=false
+korkVersion=5.3.4
+fiatVersion=1.0.4
+spinnakerGradleVersion=6.5.0

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists