Tighten the vars-argument for the ESLint no-unused-vars rule

[Snuffleupagus]

Please see https://eslint.org/docs/latest/rules/no-unused-vars#vars

[Snuffleupagus]

/botio-windows browsertest

[Snuffleupagus]

Slightly off-topic here: I've also been looking into possibly enabling the args: after-used option, however that's less straightforward unfortunately.
The reason is that we have loads of interface definitions, base classes, and placeholder methods where arguments are "unused" by design. Hence we'd likely have to add // eslint-disable-next-line no-unused-vars comments all over the code-base, which doesn't feel great, but the rule could possibly still be useful in order to find truly unused arguments!?

[pdfjsbot]

From: Bot.io (Windows)

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Received

Command cmd_test from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.193.163.58:8877/a174960c9e889a9/output.txt

[pdfjsbot]

From: Bot.io (Linux m4)

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Received

Command cmd_test from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.241.84.105:8877/1e80f2449217ca5/output.txt

[pdfjsbot]

From: Bot.io (Linux m4)

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Failed

Full output at http://54.241.84.105:8877/1e80f2449217ca5/output.txt

Total script time: 25.46 mins

• Font tests: Passed
• Unit tests: Passed
• Integration Tests: Passed
• Regression tests: FAILED

  different ref/snapshot: 6

Image differences available at: http://54.241.84.105:8877/1e80f2449217ca5/reftest-analyzer.html#web=eq.log

[pdfjsbot]

From: Bot.io (Windows)

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Failed

Full output at http://54.193.163.58:8877/a174960c9e889a9/output.txt

Total script time: 33.38 mins

• Font tests: Passed
• Unit tests: Passed
• Integration Tests: FAILED
• Regression tests: FAILED

  different ref/snapshot: 14

Image differences available at: http://54.193.163.58:8877/a174960c9e889a9/reftest-analyzer.html#web=eq.log

[calixteman]

LGTM.