Rename zuul-launcher to zuul-executor

To avoid confusion with nodepool-launcher, we've decided to rename
zuul-launcher to zuul-executor.

Change-Id: I7d03cf0f0093400f4ba2e4beb1c92694224a3e8c
Signed-off-by: Paul Belanger <pabelanger@redhat.com>
diff --git a/playbooks/tox-post.yaml b/playbooks/tox-post.yaml
index 786a984..697b727 100644
--- a/playbooks/tox-post.yaml
+++ b/playbooks/tox-post.yaml
@@ -11,7 +11,7 @@
 
     - name: Collect tox logs.
       synchronize:
-        dest: "{{ zuul.launcher.log_root }}/tox"
+        dest: "{{ zuul.executor.log_root }}/tox"
         mode: pull
         src: "{{ item.path }}/log/"
       with_items: "{{ result.files }}"