fix(Request): Safari 12.1+ supports `"same-origin"` default (#6057)
fix(Request): Safari 12.1+ supports `"same-origin"` default (#6057)

* fix(Request): Safari 12.1+ supports `"same-origin"` default

* Update Request.json

* fix lint issues
chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data,mdn/browser-compat-data