Merge pull request #14997 from rjernst/extra_config_input

Allow extra config for integ test to be anything project.file() accepts

buildSrc/src/main/groovy/org/elasticsearch/gradle/test/ClusterFormationTasks.groovy

@@ -184,6 +184,7 @@ class ClusterFormationTasks {
         Copy copyConfig = project.tasks.create(name: name, type: Copy, dependsOn: setup)
         copyConfig.into(new File(node.homeDir, 'config')) // copy must always have a general dest dir, even though we don't use it
         for (Map.Entry<String,Object> extraConfigFile : node.config.extraConfigFiles.entrySet()) {
+            Closure delayedSrc = {
                 File srcConfigFile = project.file(extraConfigFile.getValue())
                 if (srcConfigFile.isDirectory()) {
                     throw new GradleException("Source for extraConfigFile must be a file: ${srcConfigFile}")
@@ -191,8 +192,10 @@ class ClusterFormationTasks {
                 if (srcConfigFile.exists() == false) {
                     throw new GradleException("Source file for extraConfigFile does not exist: ${srcConfigFile}")
                 }
+                return srcConfigFile
+            }
             File destConfigFile = new File(node.homeDir, 'config/' + extraConfigFile.getKey())
-            copyConfig.from(srcConfigFile)
+            copyConfig.from(delayedSrc)
                       .into(destConfigFile.canonicalFile.parentFile)
                       .rename { destConfigFile.name }
         }