docs: reporting-issues.rst: reorder some steps

Reorder some steps where the order in which the readers perform them is
not crucial. This is a preparation for a later change that would make
the text much more complex otherwise.

Content just moved, not changed at all in the process.
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/r/8dfc58efde25a05ccf9bf85929826c4b1b9e09c5.1616181657.git.linux@leemhuis.infoSigned-off-by: Jonathan Corbet <corbet@lwn.net>