Installer: deallocate ports upon app uninstall

Change-Id: I19298537fed02de03a9e74fa351cf23f733de699
diff --git a/core/installer/values-tmpl/gerrit.cue b/core/installer/values-tmpl/gerrit.cue
index a2a88f9..060a7d2 100644
--- a/core/installer/values-tmpl/gerrit.cue
+++ b/core/installer/values-tmpl/gerrit.cue
@@ -106,6 +106,7 @@
 portForward: [#PortForward & {
 	allocator: input.network.allocatePortAddr
 	reservator: input.network.reservePortAddr
+	deallocator: input.network.deallocatePortAddr
 	sourcePort: input.sshPort
 	serviceName: "gerrit-gerrit-service"
 	targetPort: _sshPort