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, 1 deletions

diff --git a/main.py b/main.py
index e399ddce..1f3a7683 100755
--- a/main.py
+++ b/main.py
@@ -71,7 +71,7 @@ from subcmds import all_commands
 #
 # python-3.6 is in Ubuntu Bionic.
 MIN_PYTHON_VERSION_SOFT = (3, 6)
-MIN_PYTHON_VERSION_HARD = (3, 5)
+MIN_PYTHON_VERSION_HARD = (3, 6)
 
 if sys.version_info.major < 3:
   print('repo: error: Python 2 is no longer supported; '