feature/remove axios dependency

[karakanb]

This PR replaces the axios dependency with the Fetch API, essentially resulting in one less dependency with a reduction of ~6.8% on the bundle size, bringing the total size to 177.75KiB.

  File                          Size                   Gzipped

  dist/js/chunk-vendors.js      177.75 KiB             60.65 KiB
  dist/js/app.js                35.41 KiB              7.87 KiB
  dist/css/app.css              15.89 KiB              3.08 KiB
  dist/css/chunk-vendors.css    12.15 KiB              1.58 KiB