Non-quoted attribute value in emmet abbreviation breaks parsing with attribute later down in abbreviation

Issue Type: <b>Bug</b> In emmet abbreviations with several tag attributes included, a non-quoted attribute value causes the entire abbreviation until the next tag with an attribute to not be expanded. Expected: `a[href=#]>p>a[href=#]` should expand into: ``` <a href="#"> <p><a href="#"></a></p> </a> ``` but instead expands into: `a[href=#]>p><a href="#"></a>` I.e., it expands as if everything up until the final `a[href=#]` was ignored. This has been tried with extensions entirely disabled, with other emmet abbreviation structures, and with different attribute values, to the same result.  (edit: included recording) VS Code version: Code 1.57.1 (507ce72a4466fbb27b715c3722558bb15afa9f48, 2021-06-17T13:28:07.755Z) OS version: Windows_NT x64 10.0.19043 Restricted Mode: No <details> <summary>System Info</summary> |Item|Value| |---|---| |CPUs|Intel(R) Core(TM) i5-4690K CPU @ 3.50GHz (4 x 3498)| |GPU Status|2d_canvas: enabled<br>gpu_compositing: enabled<br>multiple_raster_threads: enabled_on<br>oop_rasterization: enabled<br>opengl: enabled_on<br>rasterization: enabled<br>skia_renderer: enabled_on<br>video_decode: enabled<br>vulkan: disabled_off<br>webgl: enabled<br>webgl2: enabled| |Load (avg)|undefined| |Memory (System)|7.94GB (1.76GB free)| |Process Argv|--crash-reporter-id 378cd57f-0e8a-4c1c-ab47-db31f5325277| |Screen Reader|no| |VM|0%| </details><details><summary>Extensions (15)</summary> Extension|Author (truncated)|Version ---|---|--- emmet-keybindings|agu|1.0.1 chronicler|arc|0.1.11 vscode-tailwindcss|bra|0.6.11 todo-tree|Gru|0.0.213 rest-client|hum|0.24.5 csharp|ms-|1.23.12 python|ms-|2021.6.944021595 vscode-pylance|ms-|2021.6.2 jupyter|ms-|2021.6.999406279 remote-wsl|ms-|0.56.5 cpptools|ms-|1.4.1 mono-debug|ms-|0.16.2 godot-csharp-vscode|nei|0.1.3 vim|vsc|1.21.3 vsc-jsonsnippets|wmo|0.9.3 </details><details> <summary>A/B Experiments</summary…