Reuse 0.11.1 and later version doesn't work with python-debian 0.1.42, pin to 0.1.40

- Related issue: https://github.com/fsfe/reuse-tool/issues/427

Change-Id: Ie64169e73d2fded97fc454afff0c4034313448be
diff --git a/requirements.txt b/requirements.txt
index 2c022db..5cc6ea1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,6 +17,7 @@
 pylint~=2.7.2
 pynetbox~=5.3.1
 python-vagrant~=0.5.15
-reuse~=0.11.1
+reuse~=0.13.0
 yamllint~=1.26.0
 zxcvbn~=4.4.28
+python-debian==0.1.40