Merge pull request apache#636 from palantir/yh/fix-maven

[SPARK-30572][BUILD] Add a fallback Maven repository

Author: yifeih

pom.xml

@@ -284,6 +284,22 @@
         <enabled>false</enabled>
       </snapshots>
     </repository>
+    <repository>
+      <id>central_without_mirror</id>
+      <!--
+        This is used as a fallback when a mirror to `central` fail.
+        For example, when we use Google Maven Central in GitHub Action as a mirror of `central`,
+        this will be used when Google Maven Central is out of sync due to its late sync cycle.
+      -->
+      <name>Maven Repository</name>
+      <url>https://repo.maven.apache.org/maven2</url>
+      <releases>
+        <enabled>true</enabled>
+      </releases>
+      <snapshots>
+        <enabled>false</enabled>
+      </snapshots>
+    </repository>
   </repositories>
   <pluginRepositories>
     <pluginRepository>