DEB: recommend polkitd-pkla

Required to prevent sleep on Debian 12, Ubuntu 24.04 LTS, and Mint 22. Cannot be depended on as the
polkitd-pkla package is not available or provided by any other package in older versions
(policykit-1 < 0.105-32).

Closes FoldingAtHome#296

SConstruct

@@ -186,6 +186,7 @@ if 'package' in COMMAND_LINE_TARGETS:
         deb_depends        = 'ca-certificates, libexpat1',
         deb_conflicts      = 'FAHClient, fahclient',
         deb_replaces       = 'FAHClient, fahclient',
+        deb_recommends     = 'polkitd-pkla',
         deb_suggests       = 'python3-websocket',
         deb_pre_depends    = 'adduser, procps',
         deb_priority       = 'optional',