kokoro: vs2022: explicitly configure x64

Change-Id: I681ed606cccd4840727c1ecbf8823827062f350d
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/76208
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Shahbaz Youssefi <syoussefi@google.com>
Reviewed-by: Shahbaz Youssefi <syoussefi@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@google.com>

tests/kokoro/gcp_windows/continuous.bat

diff --git a/tests/kokoro/gcp_windows/continuous.bat b/tests/kokoro/gcp_windows/continuous.bat
index 234c4b0..33ef8b0 100644
--- a/tests/kokoro/gcp_windows/continuous.bat
+++ b/tests/kokoro/gcp_windows/continuous.bat
@@ -20,7 +20,7 @@
 cmake --version
 
 rem To use ninja with CMake requires VC env vars
-call "C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Auxiliary\Build\vcvarsall.bat"
+call "C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Auxiliary\Build\vcvarsall.bat" x64
 rem That batch file turned echo off, so turn it back on
 @echo on