LibWeb: Use is_ascii_case_insensitive_match() where the spec says to

Author: https://github.com/AtkinsSJ
Commit: 2026ea557e
Pull-request: https://github.com/SerenityOS/serenity/pull/17502
Reviewed-by: https://github.com/linusg
Reviewed-by: https://github.com/trflynn89

Userland/Libraries/LibWeb/HTML/HTMLHyperlinkElementUtils.cpp

@@ -8,6 +8,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/HTMLHyperlinkElementUtils.h>
 #include <LibWeb/Infra/CharacterTypes.h>
+#include <LibWeb/Infra/Strings.h>
 #include <LibWeb/Loader/FrameLoader.h>
 
 namespace Web::HTML {
@@ -569,7 +570,7 @@ bool HTMLHyperlinkElementUtils::get_an_elements_noopener(StringView target) cons
 
     // 2. If element's link types do not include the opener keyword and
     //    target is an ASCII case-insensitive match for "_blank", then return true.
-    if (!link_types.contains_slow("opener"sv) && target.equals_ignoring_case("_blank"sv))
+    if (!link_types.contains_slow("opener"sv) && Infra::is_ascii_case_insensitive_match(target, "_blank"sv))
         return true;
 
     // 3. Return false.