Bump FPM action to latest commit

[bedroge]

This should solve the failing CI (see #177) for building our packages:

  #11 [6/7] RUN gem install --no-document fpm -v 1.11.0
  #11 48.39 ERROR:  Error installing fpm:
  #11 48.39 	The last version of dotenv (>= 0) to support your Ruby & RubyGems was 2.8.1. Try installing it with `gem install dotenv -v 2.8.1` and then running the current command again
  #11 48.39 	dotenv requires Ruby version >= 3.0. The current ruby version is 2.7.8.225.
  #11 48.64 Successfully installed stud-0.0.23
  #11 ERROR: process "/bin/sh -c gem install --no-document fpm -v 1.11.0" did not complete successfully: exit code: 1

[casparvl]

Well, CI passes here, that's good enough for me :)