Special characters in plotly.js causing minification and packaging issues

I have identified an issue in the plotly.js library where special characters, such as σ and μ, are used in a function. This leads to problems during the minification/packaging process, causing certain package managers to fail as they do not correctly interpret these characters.

I found a related issue in the Parcel bundler repository, which has been addressed and fixed. The details can be found here: Parcel Issue #9370

I propose modifying the original plotly.js function to replace the special characters with safer alternatives. Below is the suggested modification:

normal: function(mu, sigma) {
  var n = arguments.length;
  if (n < 2) sigma = 1;
  if (n < 1) mu = 0;
  return function() {
    var x, y, r;
    do {
      x = Math.random() * 2 - 1;
      y = Math.random() * 2 - 1;
      r = x * x + y * y;
    } while (!r || r > 1);
    return mu + sigma * x * Math.sqrt(-2 * Math.log(r) / r);
  };
},

I will try to push a PR myself

Search the plotly.js source for the normal function using the mu and sigma parameters, then review the related Parcel issue for the packaging context. Replace the problematic special-character identifiers with the proposed safer names and verify that minification and packaging no longer fail.