SPIGOT-7368: Downgrade SpecialSource version

By: md_5 <git@md-5.net>

paper-server/pom.xml

@@ -379,7 +379,7 @@
             <plugin>
                 <groupId>net.md-5</groupId>
                 <artifactId>specialsource-maven-plugin</artifactId>
-                <version>1.2.5</version>
+                <version>1.2.4</version>
                 <executions>
                     <execution>
                         <phase>package</phase>