Update python dependencies

Change-Id: Ibdd8704d5526c69f8fe4c9199c8bea3f1d92333c
diff --git a/ndncert/debian/control b/ndncert/debian/control
index fb7e4f1..668495a 100644
--- a/ndncert/debian/control
+++ b/ndncert/debian/control
@@ -3,7 +3,7 @@
 Priority: optional
 Maintainer: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
 Build-Depends: debhelper (>= 8.0.0),
- python3 (>= 3.6.0),
+ python3 (>= 3.8),
  pkg-config (>= 0.29),
  libboost-all-dev (>= 1.65.1),
  libndn-cxx-dev (>= 0.8.1),