[Backport 6.1] fix(nemesis): filter raft-topology errors when starting/stopping nodes

[mergify]

raft is generating the following errors:
raft_topology - topology change coordinator fiber got error std::runtime_error
when one of the nodes is stopped, it was decided we can safely ignore those errors

fixes: #9031

PR pre-checks (self review)

• I added the relevant backport labels
• I didn't leave commented-out/debugging code

Reminders

• Add New configuration option and document them (in sdcm/sct_config.py)
• Add unit tests to cover my changes (under unit-test/ folder)
• Update the Readme/doc folder relevant to this change (if needed)

(cherry picked from commit 2093714)

Parent PR: #9580

[mergify]

Cherry-pick of 2093714 has failed:

On branch mergify/bp/branch-6.1/pr-9580
Your branch is up to date with 'origin/branch-6.1'.

You are currently cherry-picking commit 20937149.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   sdcm/nemesis.py

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally