Fix gn for skpinfo so it can find vulkan headers.

Change-Id: I25b4751bbf70841666934d17021c507b7cf9c9be
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/419816
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 89d105b..37335b3 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2252,6 +2252,7 @@
 
   test_app("skpinfo") {
     sources = [ "tools/skpinfo.cpp" ]
+    configs = [ ":our_vulkan_headers" ]
     deps = [
       ":flags",
       ":skia",