automation: install awscli and python3-boto3 packages
This provides the `aws` command-line utility as well as a Python
library for interacting with AWS. It is useful to have these packages
installed in AMIs so you can easily interact with other AWS services.
Differential Revision: https://phab.mercurial-scm.org/D6914
Issue351: mq: qrefresh can create extra revlog entry
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ hg qinit
$ echo b > b
$ hg ci -A -m foo
adding b
$ echo cc > b
$ hg qnew -f foo.diff
$ echo b > b
$ hg qrefresh
$ hg debugindex b
rev linkrev nodeid p1 p2
0 0 1e88685f5dde 000000000000 000000000000