Update eslint config for eslint v9.2.0

[batpad]

Recently, eslint auto-upgraded, and that broke CI, with it no longer recognizing the config files.

We fixed this by pinning to an older version of eslint in this commit: 68c5451

ESLint v9.x has made some non-backwards compatible changes in how it handles config files.

@oliverroick said he'll time-box this to see if it's relatively easy to fix so that we can move to eslint 9.x, or we will continue pinning to 8.56.0 and leave this issue open.

cc @yuvipanda