Everywhere: Rename {Deprecated => Byte}String

This commit un-deprecates DeprecatedString, and repurposes it as a byte
string.
As the null state has already been removed, there are no other
particularly hairy blockers in repurposing this type as a byte string
(what it _really_ is).

This commit is auto-generated:
  $ xs=$(ack -l \bDeprecatedString\b\|deprecated_string AK Userland \
    Meta Ports Ladybird Tests Kernel)
  $ perl -pie 's/\bDeprecatedString\b/ByteString/g;
    s/deprecated_string/byte_string/g' $xs
  $ clang-format --style=file -i \
    $(git diff --name-only | grep \.cpp\|\.h)
  $ gn format $(git ls-files '*.gn' '*.gni')

Userland/Libraries/LibJS/Runtime/AggregateErrorConstructor.cpp

@@ -55,7 +55,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> AggregateErrorConstructor::construct(Fun
     // 3. If message is not undefined, then
     if (!message.is_undefined()) {
         // a. Let msg be ? ToString(message).
-        auto msg = TRY(message.to_deprecated_string(vm));
+        auto msg = TRY(message.to_byte_string(vm));
 
         // b. Perform CreateNonEnumerableDataPropertyOrThrow(O, "message", msg).
         aggregate_error->create_non_enumerable_data_property_or_throw(vm.names.message, PrimitiveString::create(vm, msg));