[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/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/ObjCStubs.kt

@@ -558,7 +558,7 @@ internal class ObjCCategoryStubBuilder(
         val description = "${category.clazz.name} (${category.name})"
         val meta = StubContainerMeta(
                 "// @interface $description",
-                "// @end; // $description"
+                "// @end // $description"
         )
         val container = SimpleStubContainer(
                 meta = meta,