update to jquery 3.6.1

[hedsnz]

Closes https://github.com/daattali/colourpicker/issues/53.

Uses latest jQuery 3.6.1 maintenance release from https://github.com/jquery/jquery/releases.

The only testing I did was to call colourWidget("red", palette = "limited", allowedCols = c("yellow", "red", "#123ABC")) (the example from the documentation) and verify that it works as expected.