Fix resize update mode being an array when resizeDelay is set

[kwy404]

When resizeDelay is set, the delayed resize runs chart.update(['resize']) instead of chart.update('resize').

Root cause: debounce in src/helpers/helpers.extras.ts schedules the delayed call with setTimeout(fn, delay, args). setTimeout passes its extra parameters to fn one by one, so fn gets the whole args array as its first argument. The branch without a delay uses fn.apply(this, args), so the two paths disagree. Because of this, the update hooks give plugins args.mode as ['resize'], scriptable options see context.mode as an array, and checks like mode !== 'resize' in the radar controller take the wrong branch.

Fix: spread the arguments, setTimeout(fn, delay, ...args), so the delayed call gets the same arguments as the direct one.

Test: a new spec in test/specs/core.controller.tests.js sets resizeDelay: 10, resizes the wrapper and expects chart.update to have been called with 'resize'. It fails before the fix (the only call was [ [ 'resize' ] ]) and passes after.