Everywhere: Add sv suffix to strings relying on StringView(char const*)

Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).

No functional changes.

Tests/LibTextCodec/TestTextDecoders.cpp

@@ -12,7 +12,7 @@ TEST_CASE(test_utf8_decode)
 {
     auto decoder = TextCodec::UTF8Decoder();
     // Bytes for U+1F600 GRINNING FACE
-    auto test_string = "\xf0\x9f\x98\x80";
+    auto test_string = "\xf0\x9f\x98\x80"sv;
 
     Vector<u32> processed_code_points;
     decoder.process(test_string, [&](u32 code_point) {