Upgrade ipython and related packages:

• https://pypi.org/project/ipython/ 7.13.0 (current as of 2020-06-05: 7.15.0)
• https://pypi.org/project/ipykernel/ 5.2.1 (current as of 2020-06-05: 5.3.0)
• https://pypi.org/project/backcall/ 0.1.0 (current as of 2020-06-05)
• https://pypi.org/project/jedi/ 0.17.0 (current as of 2020-06-05)
• https://pypi.org/project/prompt-toolkit/ 3.0.5 (current as of 2020-06-05)

All of these package versions support python >= 3.6 (note #29033).

Tarballs: see checksums.ini [upstream_url]. (To configure Sage to download from the upstream URLs, use ./configure --enable-download-from-upstream-url)

CC: @embray @jdemeyer @slel @kiwifb @timokau @antonio-rojas

Component: packages: standard

Keywords: upgrade

Author: Jonathan Kliem, John Palmieri, Antonio Rojas

Branch: e21a7b0

Reviewer: John Palmieri, Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/28197