Auto merge of #19324 - drewler:fix_matchbat, r=jdm

Get back to working dir after vcvarsall.bat

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When using cmd.exe directly (instead of `x86_x64 Cross Tools Command Prompt for VS 2017`), vcvarsall.bat changes the working directory.
To prevent this, pushd and popd could be used.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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- [X] These changes do not require tests because they are part of the build process.

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mach.bat

@@ -1,5 +1,7 @@
 @echo off
 
+pushd .
+
 IF EXIST "%ProgramFiles(x86)%" (
   set "ProgramFiles32=%ProgramFiles(x86)%"
 ) ELSE (
@@ -32,4 +34,6 @@ IF EXIST "%VS_VCVARS%" (
   EXIT /B
 )
 
+popd
+
 python mach %*