Include directive should ignore file extensions

[RaptorX]

Issue Type: Bug

• create: header.h file
  MsgBox "this is a test"

• create: source.ah2 file
  #include header.h

Result:
The highlighter says that there is an error with the include command. But there is no issue with it.

You can include any autohotkey file no matter the extension but the highlighter makes it look like you can only do ah2 which is incorrect.

Extension version: 1.2.0
VS Code version: Code 1.63.2 (899d46d82c4c95423fb7e10e68eba52050e30ba3, 2021-12-15T09:40:02.816Z)
OS version: Windows_NT x64 10.0.19043
Restricted Mode: No

System Info

Item	Value
CPUs	Intel(R) Core(TM) i5-4460 CPU @ 3.20GHz (4 x 3198)
GPU Status	2d_canvas: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: enabled_on video_decode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	31.88GB (21.98GB free)
Process Argv	D:\Cloud\OneDrive\Documents\coding\AutoHotkey\v1\SheinScrape --crash-reporter-id 99ab694c-54bb-4382-b6f7-d62cc4339404
Screen Reader	no
VM	50%

A/B Experiments

vsliv368cf:30146710
vsreu685:30147344
python383:30185418
vspor879:30202332
vspor708:30202333
vspor363:30204092
pythontb:30283811
pythonvspyt551cf:30345471
pythonptprofiler:30281270
vshan820:30294714
vstes263:30335439
vscoreces:30384385
pythondataviewer:30285071
vscod805:30301674
pythonvspyt200:30340761
binariesv615:30325510
bridge0708:30335490
bridge0723:30353136
vsaa593cf:30376535
pythonvs932:30410667
vscop804cf:30404767
vscop341:30404997
vsrem710:30416614
vscexrecpromp3t2:30407763