chore: update flake8 version from 6.0.0 to 6.1.0

[xmfcx]

This change is already done in https://github.com/tier4/pre-commit-hooks-ros/releases/tag/v0.9.0 but it is not in the main branch for some reason.

This is causing problems here:

• This PR: ci(pre-commit): autoupdate autowarefoundation/autoware_launch#1056
• https://results.pre-commit.ci/run/github/429697802/1720175089.xp-x1irGTmyerOf0_CjTuw

.github/update-sync-param-files.py:14:19: E231 missing whitespace after ':'
REPO_URL = f"https://github.com/{REPO_NAME}.git"
                  ^
1     E231 missing whitespace after ':'

And solution is to switch to flake8 6.1 as stated in this post: https://stackoverflow.com/questions/77527580/pre-commit-throwing-errors-on-missing-whitespace-after

And let's do another release (v0.10.0) with this commit.

cc. @SakodaShintaro

[SakodaShintaro]

I should have not only created tag v0.9.0, but also made a PR to push the main branch. That was my mistake.
Thank you!
LGTM