Add pinentry-gtk-2 to Apache2 AppArmor profile

Fixes freedomofpress#4362

(cherry picked from commit a7f65f9)

Author: rmol

install_files/ansible-base/roles/build-securedrop-app-code-deb-pkg/files/usr.sbin.apache2

@@ -89,6 +89,7 @@
   /usr/bin/gpg-agent rix,
   /usr/bin/gpg2 rix,
   /usr/bin/pinentry-curses rix,
+  /usr/bin/pinentry-gtk-2 rix,
   /usr/bin/python2.7 r,
   /usr/bin/srm rix,
   /usr/lib/python2.7/uuid.py r,