Improve repository settings in pom.xml regarding releases and snapshots

pom.xml

@@ -106,17 +106,45 @@
   </dependencies>
 
   <repositories>
+    <!-- the Maven central repository for releases -->
+    <repository>
+      <id>central</id>
+      <name>Maven Central</name>
+      <layout>default</layout>
+      <url>https://repo1.maven.org/maven2</url>
+      <releases>
+        <enabled>true</enabled>
+        <updatePolicy>never</updatePolicy>
+      </releases>
+      <snapshots>
+        <enabled>false</enabled>
+      </snapshots>
+    </repository>
     <!-- the official source for Spark releases, mirrored to Maven central -->
     <repository>
       <id>apache releases</id>
       <name>Apache Releases</name>
       <url>https://repository.apache.org/content/repositories/releases/</url>
+      <releases>
+        <enabled>true</enabled>
+        <updatePolicy>never</updatePolicy>
+      </releases>
+      <snapshots>
+        <enabled>false</enabled>
+      </snapshots>
     </repository>
     <!-- required to resolve Spark snapshot versions -->
     <repository>
       <id>apache snapshots</id>
       <name>Apache Snapshots</name>
       <url>https://repository.apache.org/snapshots/</url>
+      <releases>
+        <enabled>false</enabled>
+      </releases>
+      <snapshots>
+        <enabled>true</enabled>
+        <updatePolicy>daily</updatePolicy>
+      </snapshots>
     </repository>
   </repositories>