Syntax Highlighting doesn't recognize ? as part of a variable name

[JustinGrote]

Prerequisites

• I have written a descriptive issue title.
• I have searched all issues to ensure it has not already been reported.
• I have read the troubleshooting guide.
• I am sure this issue is with the extension itself and does not reproduce in a standalone PowerShell instance.
• I have verified that I am using the latest version of Visual Studio Code and the PowerShell extension.

Summary

Issue Type: Bug

? is a valid part of a variable name. Don't ask how I discovered this 😄

Extension version: 2022.1.0
VS Code version: Code 1.63.2 (899d46d82c4c95423fb7e10e68eba52050e30ba3, 2021-12-15T09:40:02.816Z)
OS version: Windows_NT x64 10.0.19044
Restricted Mode: No

System Info

Item	Value
CPUs	Intel(R) Xeon(R) CPU E5-2673 v4 @ 2.30GHz (8 x 2295)
GPU Status	2d_canvas: unavailable_software gpu_compositing: disabled_software multiple_raster_threads: enabled_on oop_rasterization: disabled_off opengl: disabled_off rasterization: disabled_software skia_renderer: enabled_on video_decode: disabled_software vulkan: disabled_off webgl: unavailable_software webgl2: unavailable_software
Load (avg)	undefined
Memory (System)	28.00GB (23.40GB free)
Process Argv	--crash-reporter-id 80b67060-e530-4dcb-b323-c415f9afc4f3
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
vsreu685:30147344
python383:30185418
vspor879:30202332
vspor708:30202333
vspor363:30204092
vswsl492:30256859
pythonvspyl392:30425749
pythontb:30283811
pythonvspyt551:30345470
pythonptprofiler:30281270
vshan820:30294714
vstes263:30335439
vscoreces:30384385
pythondataviewer:30285071
vscod805cf:30301675
pythonvspyt200:30340761
binariesv615:30325510
bridge0708:30335490
bridge0723:30353136
vsaa593:30376534
vsc1dst:30424896
pythonvs932:30410667
vscop804cf:30404767
vs360:30404995
vsrem710:30416614

PowerShell Version

Name                           Value
----                           -----
PSVersion                      7.2.1
PSEdition                      Core
GitCommitId                    7.2.1
OS                             Microsoft Windows 10.0.19044       
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visual Studio Code Version

1.63.2
899d46d82c4c95423fb7e10e68eba52050e30ba3
x64

Extension Version

powershell-preview@2022.01.0

Steps to Reproduce

$test? = 5
"$test?"

Visuals

No response

Logs

No response