Drop support for Python 3.5

Running repo with Python 3.5 fails due to the use of the encoding
parameter to subprocess.run(). There are also f-strings being used in
some of the tests.

This drops support for these systems:
* Ubuntu Xenial: released Apr 2016, EOS Apr 2021, EOL Apr 2024
* Debian Stretch: released Jun 2017, EOL Jun 2022

So the minimum required distros now are:
* Ubuntu Bionic: released Apr 2018 w/Python 3.6
* Debian Buster: released Jul 2019 w/Python 3.7

Change-Id: I1144f7ab6f882b10cac0131982df081fe4ac44f9
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/303363
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/tox.ini b/tox.ini
index 3282de14..aa4e2979 100644
--- a/tox.ini
+++ b/tox.ini
@@ -15,11 +15,10 @@
 # https://tox.readthedocs.io/
 
 [tox]
-envlist = py35, py36, py37, py38, py39
+envlist = py36, py37, py38, py39
 
 [gh-actions]
 python =
-    3.5: py35
     3.6: py36
     3.7: py37
     3.8: py38