Everywhere: Replace single-char StringView op. arguments with chars

This prevents us from needing a sv suffix, and potentially reduces the
need to run generic code for a single character (as contains,
starts_with, ends_with etc. for a char will be just a length and
equality check).

No functional changes.

Userland/DevTools/HackStudio/ProjectBuilder.cpp

@@ -246,7 +246,7 @@ void ProjectBuilder::for_each_library_dependencies(Function<void(String, Vector<
         auto library_name = result.capture_group_matches.at(0).at(0).view.string_view();
         auto dependencies_string = result.capture_group_matches.at(0).at(1).view.string_view();
 
-        func(library_name, dependencies_string.split_view(" "));
+        func(library_name, dependencies_string.split_view(' '));
     }
 }