Update a TODO comment.

Reflects a change in the test file's format.

Change-Id: Ic6f53822f6ded817bf0016049f3938be88cd7f3e
Reviewed-on: https://chromium-review.googlesource.com/690621Reviewed-by: Matt Mueller <mattm@chromium.org>
Commit-Queue: Eric Roman <eroman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#505143}

net/tools/cert_verify_tool/cert_verify_tool.cc

@@ -62,7 +62,7 @@ void PrintUsage(const char* argv0) {
 
   // TODO(mattm): allow <certs path> to be a directory containing DER/PEM files?
   // TODO(mattm): allow target to specify an HTTPS URL to check the cert of?
-  // TODO(mattm): allow target to be a verify_certificate_chain_unittest PEM
+  // TODO(mattm): allow target to be a verify_certificate_chain_unittest .test
   // file?
 }