Web: Add Hr Element (#741)

* Add Hr element

* Add Hr Tag

* Add missing HRElement import

* Remove the forbidden content

web/core/src/jsMain/kotlin/androidx/compose/web/attributes/Attrs.kt

@@ -12,6 +12,7 @@ interface Tag {
     object Option : Tag
     object OptGroup : Tag
     object H : Tag
+    object Hr : Tag
     object Ul : Tag
     object Ol : Tag
     object Li : Tag

web/core/src/jsMain/kotlin/androidx/compose/web/elements/Elements.kt

@@ -22,6 +22,7 @@ import org.w3c.dom.HTMLDivElement
 import org.w3c.dom.HTMLElement
 import org.w3c.dom.HTMLFormElement
 import org.w3c.dom.HTMLHeadingElement
+import org.w3c.dom.HTMLHRElement
 import org.w3c.dom.HTMLImageElement
 import org.w3c.dom.HTMLInputElement
 import org.w3c.dom.HTMLLIElement
@@ -358,6 +359,17 @@ fun Footer(
     )
 }
 
+@Composable
+fun Hr(
+    attrs: AttrBuilderContext<Tag.Hr> = {}
+) {
+    TagElement<Tag.Hr, HTMLHRElement>(
+        tagName = "hr", 
+        applyAttrs = attrs, 
+        content = null
+    )
+}
+
 @Composable
 fun Label(
     forId: String? = null,