Filter correctly for empty destinations

An empty destination should only filter container with empty
destination, not pick up all containers.

Fixes: https://github.com/basecamp/kamal/issues/1184

lib/kamal/commands/app.rb

@@ -47,7 +47,7 @@ class Kamal::Commands::App < Kamal::Commands::Base
   end
 
   def info
-    docker :ps, *filter_args
+    docker :ps, *container_filter_args
   end
 
 
@@ -67,7 +67,7 @@ class Kamal::Commands::App < Kamal::Commands::Base
 
   def list_versions(*docker_args, statuses: nil)
     pipe \
-      docker(:ps, *filter_args(statuses: statuses), *docker_args, "--format", '"{{.Names}}"'),
+      docker(:ps, *container_filter_args(statuses: statuses), *docker_args, "--format", '"{{.Names}}"'),
       extract_version_from_name
   end
 
@@ -91,11 +91,15 @@ class Kamal::Commands::App < Kamal::Commands::Base
     end
 
     def latest_container(format:, filters: nil)
-      docker :ps, "--latest", *format, *filter_args(statuses: ACTIVE_DOCKER_STATUSES), argumentize("--filter", filters)
+      docker :ps, "--latest", *format, *container_filter_args(statuses: ACTIVE_DOCKER_STATUSES), argumentize("--filter", filters)
     end
 
-    def filter_args(statuses: nil)
-      argumentize "--filter", filters(statuses: statuses)
+    def container_filter_args(statuses: nil)
+      argumentize "--filter", container_filters(statuses: statuses)
+    end
+
+    def image_filter_args
+      argumentize "--filter", image_filters
     end
 
     def extract_version_from_name
@@ -103,13 +107,17 @@ class Kamal::Commands::App < Kamal::Commands::Base
       %(while read line; do echo ${line##{role.container_prefix}-}; done)
     end
 
-    def filters(statuses: nil)
+    def container_filters(statuses: nil)
       [ "label=service=#{config.service}" ].tap do |filters|
-        filters << "label=destination=#{config.destination}" if config.destination
+        filters << "label=destination=#{config.destination}"
         filters << "label=role=#{role}" if role
         statuses&.each do |status|
           filters << "status=#{status}"
         end
       end
     end
+
+    def image_filters
+      [ "label=service=#{config.service}" ]
+    end
 end

lib/kamal/commands/app/containers.rb

@@ -2,7 +2,7 @@ module Kamal::Commands::App::Containers
   DOCKER_HEALTH_LOG_FORMAT    = "'{{json .State.Health}}'"
 
   def list_containers
-    docker :container, :ls, "--all", *filter_args
+    docker :container, :ls, "--all", *container_filter_args
   end
 
   def list_container_names
@@ -20,7 +20,7 @@ module Kamal::Commands::App::Containers
   end
 
   def remove_containers
-    docker :container, :prune, "--force", *filter_args
+    docker :container, :prune, "--force", *container_filter_args
   end
 
   def container_health_log(version:)

lib/kamal/commands/app/images.rb

@@ -4,7 +4,7 @@ module Kamal::Commands::App::Images
   end
 
   def remove_images
-    docker :image, :prune, "--all", "--force", *filter_args
+    docker :image, :prune, "--all", "--force", *image_filter_args
   end
 
   def tag_latest_image