env/windows-arm64/azure: fix buglet in VM setup script

Add back in a missing "$here = Get-Location" needed during
python setup (deleted in a previous CL by accident).

Change-Id: I8cc95b9d34391ac2df039e737bdc9dbf8001f44b
Reviewed-on: https://go-review.googlesource.com/c/build/+/549715
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
diff --git a/env/windows-arm64/azure/startup.ps1 b/env/windows-arm64/azure/startup.ps1
index 8b1ba86..e36c6e7 100644
--- a/env/windows-arm64/azure/startup.ps1
+++ b/env/windows-arm64/azure/startup.ps1
@@ -170,6 +170,7 @@
 # "bootstrapswarm" requires that "python3" be on the path, not just "python",
 # and annoyingly, choco only installed python.exe. Create a symbolic link
 # by hand.
+$here = Get-Location
 Set-Location C:\Python311
 New-Item -ItemType SymbolicLink -Path "python3.exe" -Target "python.exe"
 Set-Location $here