closes https://github.com/TryGhost/Ghost/issues/8384
- fixes image uploads on settings/general by reverting to jQuery for triggering the file dialog because IE11 doesn't support `MouseEvent` events or have the `.closest` method on native DOM elements
- gives all SVG elements an explicit `width` and `height` - if one property is set to `auto` or not specified IE11 will treat it as 100% of the container
- fixes horizontal scroll + scrollbar on the main app viewport
- Modal button position tweaked, removed extraneous margin
- Fix user profile full name field and mobile profile-picture
- Added chevron to tag settings men, corrected chevron colour
- Fixed regression in delete-tag button caused by removing flexbox from buttons
- Fixed regression in button positioning on about-ghost page caused by removing flexbox from buttons
See #5652
