LibWeb: Expect IDL namespace to end with semicolon

From the Web IDL spec: https://heycam.github.io/webidl/#prod-Namespace

Namespace ::
    namespace identifier { NamespaceMembers } ;

Libraries/LibWeb/DOM/CharacterData.idl

@@ -6,4 +6,4 @@ interface CharacterData : Node {
     readonly attribute Element? nextElementSibling;
     readonly attribute Element? previousElementSibling;
 
-}
+};

Libraries/LibWeb/DOM/Comment.idl

@@ -1,3 +1,3 @@
 interface Comment : CharacterData {
 
-}
+};

Libraries/LibWeb/DOM/DOMImplementation.idl

@@ -4,4 +4,4 @@ interface DOMImplementation {
 
     boolean hasFeature();
 
-}
+};

Libraries/LibWeb/DOM/Document.idl

@@ -34,4 +34,4 @@ interface Document : Node {
 
     attribute DOMString title;
 
-}
+};

Libraries/LibWeb/DOM/DocumentFragment.idl

@@ -8,4 +8,4 @@ interface DocumentFragment : Node {
     Element? querySelector(DOMString selectors);
     ArrayFromVector querySelectorAll(DOMString selectors);
 
-}
+};

Libraries/LibWeb/DOM/DocumentType.idl

@@ -4,4 +4,4 @@ interface DocumentType : Node {
     readonly attribute DOMString publicId;
     readonly attribute DOMString systemId;
 
-}
+};

Libraries/LibWeb/DOM/Element.idl

@@ -17,4 +17,4 @@ interface Element : Node {
 
     readonly attribute Element? nextElementSibling;
     readonly attribute Element? previousElementSibling;
-}
+};

Libraries/LibWeb/DOM/Event.idl

@@ -20,4 +20,4 @@ interface Event {
 
     readonly attribute boolean isTrusted;
 
-}
+};

Libraries/LibWeb/DOM/EventTarget.idl

@@ -3,4 +3,4 @@ interface EventTarget {
     void addEventListener(DOMString type, EventListener? callback);
     void removeEventListener(DOMString type, EventListener? callback);
 
-}
+};

Libraries/LibWeb/DOM/Node.idl

@@ -12,5 +12,5 @@ interface Node : EventTarget {
     Node appendChild(Node node);
     Node insertBefore(Node node, Node? child);
 
-}
+};
 

Libraries/LibWeb/DOM/ShadowRoot.idl

@@ -3,4 +3,4 @@ interface ShadowRoot : DocumentFragment {
     readonly attribute DOMString mode;
     readonly attribute Element host;
 
-}
+};

Libraries/LibWeb/DOM/Text.idl

@@ -1,3 +1,3 @@
 interface Text : CharacterData {
 
-}
+};