Bump django from 1.9.13 to 1.11.29 in /sample_project

Bumps [django](https://github.com/django/django) from 1.9.13 to 1.11.29.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@1.9.13...1.11.29)

Signed-off-by: dependabot[bot] <support@github.com>

sample_project/requirements.txt

@@ -1,3 +1,3 @@
 boto==2.46.1
-Django==1.9.13
+Django==1.11.29
 django-webpacker==0.1.1