Revert "Move to released Iceberg (apache#926) (apache#951)"

This reverts commit 03c75ef.

Author: dongjoon-hyun

pom.xml

@@ -194,7 +194,7 @@
     <selenium.version>3.141.59</selenium.version>
     <htmlunit.version>2.40.0</htmlunit.version>
     <acispark.callhome.version>0.2.0</acispark.callhome.version>
-    <iceberg.version>0.12.0-apple-preview-2</iceberg.version>
+    <iceberg.version>0.12.0-apple-preview-2-SNAPSHOT</iceberg.version>
     <!--
     Managed up from older version from Avro; sync with jackson-module-paranamer dependency version
     -->
@@ -294,6 +294,10 @@
       <id>apple</id>
       <url>https://artifacts.apple.com/libs-release</url>
     </repository>
+    <repository>
+      <id>apple-snapshot</id>
+      <url>https://artifacts.apple.com/libs-snapshot</url>
+    </repository>
   </repositories>
   <pluginRepositories>
     <pluginRepository>

project/SparkBuild.scala

@@ -270,6 +270,7 @@ object SparkBuild extends PomBuild {
       "gcs-maven-central-mirror" at "https://maven-central.storage-download.googleapis.com/maven2/",
       DefaultMavenRepository,
       "apple" at "https://artifacts.apple.com/libs-release",
+      "apple-snapshot" at "https://artifacts.apple.com/libs-snapshot",
       Resolver.mavenLocal,
       Resolver.file("ivyLocal", file(Path.userHome.absolutePath + "/.ivy2/local"))(Resolver.ivyStylePatterns)
     ),