(GH-819) Revert TMPDIR changes

This commit reverts the modification of the TMPDIR environment variable
from the previous release. This change was made to fix a bug in
docker compose where some processes would fail if the noexec bit had
been set on /tmp. However this change caused unexpected failures in
certain environments.

Author: chelnak

lib/puppet/provider/docker_compose/ruby.rb

@@ -14,8 +14,7 @@
   end
 
   has_command(:docker_compose, command(:dockercompose)) do
-    Dir.mkdir('/tmp_docker') unless Dir.exist?('/tmp_docker')
-    ENV.store('TMPDIR', '/tmp_docker')
+    environment(HOME: '/root')
   end
 
   def exists?