chore(ci): set pinact cooldown to only 6 days

[flub]

Description

Currently dependabot upgrades after 7 days, but pinact uses a slightly
different cutoff time and sometimes we get a failure by just a few
hours. 6 days is enough of a cooldown, so instead of extending
dependabot let's shorten pinact.

API Changes

n/a

Notes & open questions

n/a

Change checklist

• Self-review.
• Documentation updates following the style guide, if relevant.
• Tests if relevant.
• All API changes documented.
• This PR was created by a human that thought critically about the
  proposed change and wrote an as clear and concise description as
  they could.
• This PR isn't slop, and is carefully crafted to do have the
  intented effect.
• cargo make passes locally.

[github-actions]

Documentation for this PR has been generated and is available at: https://n0-computer.github.io/net-tools/pr/242/docs/net_tools/

Last updated: 2026-10-01T14:11:16Z

[flub]

see https://github.com/n0-computer/net-tools/actions/runs/36859700908/job/110360602989?pr=238 from #238 for the example that triggered this