Fixed few things...

Author: RealMangorage

src/main/java/org/mangorage/mangobotcore/plugin/api/Metadata.java

@@ -9,5 +9,5 @@ public sealed interface Metadata permits MetadataImpl {
     String getName();
     String getType();
     String getVersion();
-    List<Dependency> getDependencies();
+    List<? extends Dependency> getDependencies();
 }

src/main/java/org/mangorage/mangobotcore/plugin/internal/MetadataImpl.java

@@ -21,7 +21,7 @@ public record MetadataImpl(
         String version,
 
         @Expose
-        List<Dependency> dependencies
+        List<DependencyImpl> dependencies
 ) implements Metadata {
 
 
@@ -47,7 +47,7 @@ public String getVersion() {
     }
 
     @Override
-    public List<Dependency> getDependencies() {
+    public List<DependencyImpl> getDependencies() {
         return dependencies;
     }
 }