MFH: r538100

www/chromium: Update to version 83.0.4103.97

Submitted by: Matthias Wolf <freebsd@rheinwolf.de> via [1]
Approved by: portmgr (blanket security fix), chromium@ (rene)
Security: https://chromereleases.googleblog.com/2020/06/stable-channel-update-for-desktop.html

[1] https://github.com/gliaskos/freebsd-chromium