Add swapnilgupta@google.com to policy owners

Change-Id: Iece3b62d60f61bccbeb5e47a04e1447de652814b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2387761Reviewed-by: Sergey Poromov <poromov@chromium.org>
Commit-Queue: Swapnil Gupta <swapnilgupta@google.com>
Cr-Commit-Position: refs/heads/master@{#804717}

chrome/browser/chromeos/policy/OWNERS

 file://chromeos/policy/OWNERS
 
+per-file *install_event*=swapnilgupta@google.com
+
 # COMPONENT: Enterprise