package/python3: bump to version 3.8.2

Bugfix release, fixing a number of issues.  For details, see the
announcement:

https://docs.python.org/release/3.8.2/whatsnew/changelog.html#python-3-8-2-final



Adjust the spacing in the hash file and update the hash of the license file
for a change in copyright years:

-2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Python Software Foundation;
+2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Python Software Foundation;

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>