[KT-52681] Remove unnecessary semicolon after Objective-C @end

Objective-c `@end` doesn't need a semicolon, however KMM exported header
file, for instance:
```
__attribute__((swift_name("KotlinIterator")))
@protocol MyProjectKotlinIterator
@required
- (BOOL)hasNext __attribute__((swift_name("hasNext()")));
- (id _Nullable)next __attribute__((swift_name("next()")));
@end;
```
This creates problems with some code checkers that will not expect it
there, so it seems best to remove it.

kotlin-native/runtime/src/main/cpp/ObjCExportErrors.mm

@@ -139,13 +139,13 @@ extern "C" OBJ_GETTER(Kotlin_ObjCExport_NSErrorAsException, id error) {
 }
 
 @interface NSError (NSErrorKotlinException)
-@end;
+@end
 
 @implementation NSError (NSErrorKotlinException)
 -(id)kotlinException {
   auto userInfo = self.userInfo;
   return userInfo == nullptr ? nullptr : userInfo[@"KotlinException"];
 }
-@end;
+@end
 
 #endif

kotlin-native/runtime/src/main/cpp/ObjCExportPrivate.h

@@ -16,7 +16,7 @@
 
 @interface KotlinBase : NSObject <NSCopying>
 +(instancetype)createRetainedWrapper:(ObjHeader*)obj;
-@end;
+@end
 
 enum class ReleaseMode {
     kRelease,

kotlin-native/runtime/src/main/cpp/ObjCInterop.mm

@@ -61,7 +61,7 @@ struct KotlinObjCClassData {
 @protocol HasKotlinObjCClassData
 @required
 -(void*)_kotlinObjCClassData;
-@end;
+@end
 
 static inline struct KotlinObjCClassData* GetKotlinClassData(id objOrClass) {
   void* ptr = [(id<HasKotlinObjCClassData>)objOrClass _kotlinObjCClassData];