(maint) Update acceptance tests to run without service

By relying on the puppet service to upgrade puppet we lose all logging
info in case something fails, which makes things difficult to debug.
Change to run with puppet agent -t.

We can also fix the logging part by configuring puppet to log to a file,
then printing the contents of the file.

acceptance/helpers.rb

@@ -347,7 +347,7 @@ def wait_for_installation_pid(host)
         end
 
         step "(Agent) waiting for upgrade pid file to be created..." do
-          retry_on(host, "cat #{upgrade_pidfile}", {:max_retries => 5, :retry_interval => 2})
+          retry_on(host, "cat #{upgrade_pidfile}", {:max_retries => 10, :retry_interval => 2})
         end
 
         step "(Agent) waiting for upgrade to complete..." do

acceptance/tests/test_upgrade_puppet5_to_puppet6.rb

@@ -18,7 +18,8 @@ class { puppet_agent:
     apt_source      => 'http://nightlies.puppet.com/apt',
     yum_source      => 'http://nightlies.puppet.com/yum',
     windows_source  => 'http://nightlies.puppet.com/downloads',
-    collection      => 'puppet6-nightly'
+    collection      => 'puppet6-nightly',
+    service_names   => []
   }
 }
     PP
@@ -39,9 +40,15 @@ class { puppet_agent:
 
   step "Upgrade the agents from Puppet 5 to Puppet 6..." do
     agents_only.each do |agent|
-      start_puppet_service_and_wait_for_puppet_run(agent)
+      on(agent, puppet("agent -t --debug"), acceptable_exit_codes: 2)
       wait_for_installation_pid(agent)
       assert_agent_version_on(agent, latest_version.scan(/6\.\d*\.\d*\.\d*/).first)
     end
   end
+
+  step "Run again for idempotency" do
+    agents_only.each do |agent|
+      on(agent, puppet("agent -t --debug"), acceptable_exit_codes: 0)
+    end
+  end
 end

acceptance/tests/test_upgrade_puppet6_to_puppet7.rb

@@ -18,7 +18,8 @@ class { puppet_agent:
     apt_source      => 'http://nightlies.puppet.com/apt',
     yum_source      => 'http://nightlies.puppet.com/yum',
     windows_source  => 'http://nightlies.puppet.com/downloads',
-    collection      => 'puppet7-nightly'
+    collection      => 'puppet7-nightly',
+    service_names   => []
   }
 }
     PP
@@ -39,9 +40,15 @@ class { puppet_agent:
 
   step "Upgrade the agents from Puppet 6 to Puppet 7..." do
     agents_only.each do |agent|
-      start_puppet_service_and_wait_for_puppet_run(agent)
+      on(agent, puppet("agent -t --debug"), acceptable_exit_codes: 2)
       wait_for_installation_pid(agent)
       assert_agent_version_on(agent, latest_version.scan(/7\.\d*\.\d*\.\d*/).first)
     end
   end
+
+  step "Run again for idempotency" do
+    agents_only.each do |agent|
+      on(agent, puppet("agent -t --debug"), acceptable_exit_codes: 0)
+    end
+  end
 end