Remove polyfill io.

This was vestigial - it looks like it was not included prior to the change in ownership. However, we still reference polyfill io in documentation and make a wget against it in CDN. Removing.

Author: sampottinger

README.md

@@ -139,7 +139,6 @@ The project uses the following:
  - [Matplotlib](https://matplotlib.org/) under the [PSF License](https://matplotlib.org/stable/users/project/license.html).
  - [Pandas](https://pandas.pydata.org/) under the [BSD License](https://github.com/pandas-dev/pandas/blob/main/LICENSE).
  - [Papa Parse](https://www.papaparse.com/) under the [MIT License](https://github.com/mholt/PapaParse/blob/master/LICENSE).
- - [Polyfill.io](https://polyfill.io/v3/) under the [MIT License](https://github.com/JakeChampion/polyfill-service/blob/main/LICENSE.md).
  - [Popper](https://popper.js.org/) under the [MIT License](https://github.com/floating-ui/floating-ui/blob/master/LICENSE).
  - [Pure CSS Custom Dropdown Arrow](https://codepen.io/code-boxx/pen/RwxbpOz) under the [MIT License](https://codepen.io/code-boxx/pen/RwxbpOz).
  - [Qunit](https://qunitjs.com/) under the [MIT License](https://github.com/qunitjs/qunit/blob/main/LICENSE.txt).

support/load_deps.sh

@@ -16,8 +16,6 @@ mkdir -p third_party
 [ ! -e third_party/tippy.min.js ] && wget https://unpkg.com/tippy.js@6.3.7/dist/tippy-bundle.umd.min.js -O third_party/tippy.min.js
 [ ! -e third_party/js.cookie.min.js ] && wget https://cdn.jsdelivr.net/npm/js-cookie@3.0.5/dist/js.cookie.min.js -O third_party/js.cookie.min.js
 
-[ ! -e third_party/pollyfill.min.js ] && wget https://polyfill.io/v3/polyfill.min.js?features=es2015%2Ces2016%2Ces2017%2Ces2018%2Ces2019%2Ces2020%2Ces2021%2Ces2022%2Ces5%2Ces6%2Ces7%2CResizeObserver -O third_party/pollyfill.min.js
-
 [ ! -e third_party/es-module-shims.js ] && wget https://ga.jspm.io/npm:es-module-shims@1.8.0/dist/es-module-shims.js -O third_party/es-module-shims.js
 
 [ ! -e third_party/ua-parser.min.js ] && wget https://cdnjs.cloudflare.com/ajax/libs/UAParser.js/1.0.36/ua-parser.min.js -O third_party/ua-parser.min.js