Increase default cache time

.gnupg/gpg-agent.conf

-default-cache-ttl 7200
-max-cache-ttl 7200
+# Change default timeout in seconds to
+# 6 * 3600 = 21600 6 hours
+default-cache-ttl 21600
+max-cache-ttl 21600
 enable-ssh-support
 # MUST be a full path
 # pinentry-program /usr/bin/pinentry-tty