Use 'composer_home_path' during auth.json generation

tasks/oauth.yml

@@ -3,5 +3,5 @@
 - name: Configure github oauth token
   template:
     src: ".composer/auth.json.j2"
-    dest: "~/.composer/auth.json"
+    dest: "{{ composer_home_path|default('~/.composer') }}/auth.json"
   when: composer_github_oauth != false