Add self to pull_requests.toml (model-checking#65)

As mentioned elsewhere, add self to list of people willing to help
evaluate submissions.

By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache 2.0 and MIT licenses.

.github/pull_requests.toml

@@ -9,5 +9,6 @@ members = [
     "remi-delmas-3000",
     "qinheping",
     "tautschnig",
-    "jaisnan"
+    "jaisnan",
+    "patricklam"
 ]