[build] Remove OSS Sonatype Snapshot repository

Having the OSS Sonatype Snapshot repository searched causes build
failures if there snapshot dependencies are resolved due the javadoc
linking:

javadoc: error - Error fetching URL: https://jxmpp.org/releases/1.0.3-SNAPSHOT/javadoc/
> Task :javadocAll
javadoc: error - Error fetching URL: https://minidns.org/releases/1.0.2-SNAPSHOT/javadoc/
2 errors

build.gradle

@@ -172,10 +172,6 @@ allprojects {
 	repositories {
 		mavenLocal()
 		mavenCentral()
-		// Add OSS Sonatype Snapshot repository
-		maven {
-			url 'https://oss.sonatype.org/content/repositories/snapshots'
-		}
 	}
 
 	tasks.withType(JavaCompile) {