__package_pip: update man.rst

Adjusted comments for `explorer/extras` and updated the man page for the
new behaviour of updating the extras.
3 jobs for feature/__package_pip/extras in 1 minute and 15 seconds (queued for 32 seconds)
Status Job ID Name Coverage
  Test
passed #7869
pycodestyle

00:00:23

passed #7868
shellcheck

00:00:24

passed #7870
unit_tests

00:00:27