VsDevCmdGenerator: respect the user's startingDirectory (#15035)

The PowerShell equivalent was added in the initial pull request, #7774.

Closes #13721

(cherry picked from commit f06cd17)
Service-Card-Id: 88719282
Service-Version: 1.17

.github/actions/spelling/expect/expect.txt

@@ -1776,6 +1776,7 @@ srv
 srvinit
 srvpipe
 ssa
+startdir
 STARTF
 STARTUPINFO
 STARTUPINFOEX

src/cascadia/TerminalSettingsModel/VsDevCmdGenerator.cpp

@@ -42,6 +42,9 @@ std::wstring VsDevCmdGenerator::GetProfileCommandLine(const VsSetupConfiguration
     commandLine.reserve(256);
     commandLine.append(LR"(cmd.exe /k ")");
     commandLine.append(GetDevCmdScriptPath(instance));
+    // The "-startdir" parameter will prevent "vsdevcmd" from automatically
+    // setting the shell path so the path in the profile will be used instead.
+    commandLine.append(LR"(" -startdir=none)");
 #if defined(_M_ARM64)
     commandLine.append(LR"(" -arch=arm64 -host_arch=x64)");
 #elif defined(_M_AMD64)