Do not invoke healthcheck on deploy when no web role

lib/kamal/cli/healthcheck.rb

@@ -3,7 +3,7 @@ class Kamal::Cli::Healthcheck < Kamal::Cli::Base
 
   desc "perform", "Health check current app version"
   def perform
-    return unless KAMAL.primary_role.running_traefik?
+    raise "The primary host is not configured to run Traefik" unless KAMAL.config.primary_role.running_traefik?
     on(KAMAL.primary_host) do
       begin
         execute *KAMAL.healthcheck.run

lib/kamal/cli/main.rb

@@ -38,8 +38,10 @@ class Kamal::Cli::Main < Kamal::Cli::Base
         say "Ensure Traefik is running...", :magenta
         invoke "kamal:cli:traefik:boot", [], invoke_options
 
-        say "Ensure app can pass healthcheck...", :magenta
-        invoke "kamal:cli:healthcheck:perform", [], invoke_options
+        if KAMAL.config.primary_role.running_traefik?
+          say "Ensure app can pass healthcheck...", :magenta
+          invoke "kamal:cli:healthcheck:perform", [], invoke_options
+        end
 
         say "Detect stale containers...", :magenta
         invoke "kamal:cli:app:stale_containers", [], invoke_options.merge(stop: true)

lib/kamal/commands/healthcheck.rb

@@ -2,7 +2,6 @@ class Kamal::Commands::Healthcheck < Kamal::Commands::Base
 
   def run
     web = config.role(:web)
-    return unless web.present?
 
     docker :run,
       "--detach",