HTML coloring and autocompletion: "srcset" is missing

[llopez-edu]

Description of the Issue

When writing an HTML file, the keyword "srcset" (see https://developer.mozilla.org/en-US/docs/Web/HTML/Element/source#srcset ) is missing from text completion and colour scheme.

Steps to Reproduce the Issue

1. Open a new buffer. Set the language to HTML.
2. Type the following line: <source srcset="example.png" media="(orientation: portrait)">

Expected Behavior

Both "srcset" and "media" should be highlighted as keywords (attribute names).

Actual Behavior

Only "media" is recognized as a keyword:

Debug Information

Notepad++ v8.5.8 (64-bit)
Build time : Oct 15 2023 - 21:43:56
Path : C:\Program Files\Notepad++\notepad++.exe
Command Line : "C:\Program Files\Notepad++\change.log"
Admin mode : ON
Local Conf mode : OFF
Cloud Config : OFF
OS Name : Windows 10 Enterprise (64-bit)
OS Version : 21H1
OS Build : 19043.2364
Current ANSI codepage : 1252
Plugins :
mimeTools (2.9)
NppConverter (4.5)
NppExport (0.4)

Issue inspired by #12416