Update Maven repository URL for velocity

Author: matsu1213

pom.xml

@@ -70,7 +70,7 @@
     </repository>
     <repository>
       <id>velocity</id>
-      <url>https://nexus.velocitypowered.com/repository/maven-public/</url>
+      <url>https://repo.papermc.io/repository/maven-public/</url>
     </repository>
   </repositories>