deps: Upgrade debug to 2.6.9

[PatOnTheBack]

Summary

This fixes a ReDoS vulnerability in debug 2.6.8

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[brendankenny]

• it looks like we'd need CLA information from @snyk-test, the author of the commit. We have one from snyk-bot...any way to switch to that user? Or to get a CLA for @snyk-test.
• I'd call this more of a corner-case performance improvement than a DoS fix :)
• Is this an automated service? It would be good to link to any info about who is running this, etc in the profile if so.
• I'm also not sure we want to sign up for automated PRs.

[PatOnTheBack]

@brendankenny Yes, Snyk is an automated service from the GitHub marketplace. You can find out about it here: https://snyk.io/

[brendankenny]

@brendankenny Yes, Snyk is an automated service from the GitHub marketplace. You can find out about it here: https://snyk.io/

yes, I was wondering if you were a bot, but apparently not :)

[paulirish]

thanks. i'll take care of this in #9398