[feat] Remove puppet run stages

To reduce complexity, let's get rid of run stages.
We used them earlier but they seem to have no purpose anymore.

There was two stage leftovers:

- `site_config::slow` did an `apt-get dist-upgrade` in the
  `setup` stage
- `site_config::setup` did call the `site_config::hosts` class
  in the `setup` stage

I checked for dependencies to to those resources, and it looks good,
i tested by triggering a citest.

From
https://docs.puppetlabs.com/puppet/latest/reference/lang_run_stages.html#limitations-and-known-issues:

```
Due to these limitations, stages should only be used with the simplest
of classes, and only when absolutely necessary. Mass dependencies like
package repositories are effectively the only valid use case.
```

1 files changed, 4 insertions, 3 deletions

diff --git a/puppet/modules/site_config/manifests/slow.pp b/puppet/modules/site_config/manifests/slow.pp
index 94bac88d..3650eb19 100644
--- a/puppet/modules/site_config/manifests/slow.pp
+++ b/puppet/modules/site_config/manifests/slow.pp
@@ -1,6 +1,7 @@
+# this class is run by default, but can be excluded
+# for testing purposes by calling "leap deploy" with
+# the "--fast" parameter
 class site_config::slow {
   tag 'leap_slow'
-  class { 'site_apt::dist_upgrade':
-    stage => setup,
-  }
+  class { 'site_apt::dist_upgrade': }
 }