Libraries: Use default constructors/destructors in LibWeb

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#cother-other-default-operation-rules

"The compiler is more likely to get the default semantics right and
you cannot implement these functions better than the compiler."

Userland/Libraries/LibWeb/HTML/HTMLTableSectionElement.cpp

@@ -18,9 +18,7 @@ HTMLTableSectionElement::HTMLTableSectionElement(DOM::Document& document, DOM::Q
 {
 }
 
-HTMLTableSectionElement::~HTMLTableSectionElement()
-{
-}
+HTMLTableSectionElement::~HTMLTableSectionElement() = default;
 
 // https://html.spec.whatwg.org/multipage/tables.html#dom-tbody-rows
 NonnullRefPtr<DOM::HTMLCollection> HTMLTableSectionElement::rows() const