Add javassist to the libraries for future use. Apologies for the like extra 600kb :(

pom.xml

@@ -105,6 +105,10 @@
                             <pattern>com.google.gson</pattern>
                             <shadedPattern>us.myles.viaversion.libs.gson</shadedPattern>
                         </relocation>
+                        <relocation>
+                            <pattern>org.javassist</pattern>
+                            <shadedPattern>us.myles.viaversion.libs.javassist</shadedPattern>
+                        </relocation>
                     </relocations>
                 </configuration>
                 <executions>
@@ -157,6 +161,15 @@
             </exclusions>
         </dependency>
 
+        <!-- Javassist (Bytecode Library) -->
+        <dependency>
+            <groupId>org.javassist</groupId>
+            <artifactId>javassist</artifactId>
+            <version>3.20.0-GA</version>
+            <scope>compile</scope>
+            <optional>true</optional>
+        </dependency>
+
         <!-- NBT Edit Library -->
         <dependency>
             <groupId>org.spacehq</groupId>