"Error" in provided XML document STL.natvis

Bug type: Debugger

Describe the bug

• OS and Version: Windows 10
• VS Code Version: 1.61.0
• C/C++ Extension Version: 1.7.0
• Other extensions you installed (and if the issue persists after disabling them): N/A

Error "There is an error in the XML document (281, 41)." while reading file: C:\Users\{user}\.vscode\extensions\ms-vscode.cpptools-1.7.0\debugAdapters\vsdbg\bin\Visualizers\STL.natvis"

To Reproduce
Please include a code sample and launch.json configuration.
Steps to reproduce the behavior:

1. Build LLVM, clang and lldb with libxml2 for Windows *huge pain (llvm-projects fault here really. Necessary for both lldb-mi and for an appropriate version of python).
2. Build the lldb-mi with the toolchain just built.
3. Compile c++ program via clang -glldb main.cpp -o main.exe
4. launch the program with the launch.json configuration provided below
5. Change tabs to the debug console and see the error at the top. It appears that the Priority attribute for Type isn't being handled.

{
	"name": "(lldb) Launch",
	"type": "cppdbg",
	"request": "launch",
	"program": "${workspaceFolder}/main.exe",
	"targetArchitecture": "x64",
	"args": [],
	"stopAtEntry": false,
	"cwd": "${workspaceFolder}",
	"environment": [],
	"MIMode": "lldb",
	"miDebuggerPath": "lldb-mi.exe",
	"externalConsole": false,
	"showDisplayString": true,
	"visualizerFile": "C:\\Users\\{user}\\.vscode\\extensions\\ms-vscode.cpptools-1.7.0\\debugAdapters\\vsdbg\\bin\\Visualizers\\STL.natvis",
}

Additional context
This is on a system without internet. As such I am unable to provide any log files. Please also disregard any typos in the provided launch config as it was typed by hand.

I can't seem to find where the visualizer files are being handled in the repo. I would like to be able to patch fix it into the extension on my local machine if at all possible but if I need to wait for another release it is understandable.

Start by inspecting the STL.natvis file at line 281 and the debugger visualizer handling used with lldb-mi. Reproduce with the provided launch.json configuration and confirm how the Priority attribute is parsed. Done means the visualizer loads without the XML error in the debug console.