docs(usage-cli): add jwtSignOptions (#323)

Author: dargmuesli

Diff for: src/pages/postgraphile/usage-cli.md

@@ -285,6 +285,7 @@ Here is the list of keys and their default values, or types, supported in the
   jwtAudiences: <string>
   jwtRole = ['role']
   jwtSecret: <string>
+  jwtSignOptions: {}
   jwtTokenIdentifier
   jwtVerifyAlgorithms: <string>
   jwtVerifyAudience: <string>