[Feature] Update icons for link component

Description of Change

Updated link-related icons: Calendar, Directions, External Link, PaperClip (attachments), Phone, TTY (formerly PhoneTTY), Text
Got rid of special folder for link-related icons as they are no longer special in-circle variants--an icon is an icon
- Long term, the logo and branch emblems are the only SVGs that should have their own folder as they are actually purposefully unique
Removed the following icons as unnecessary:
- UploadPhoto - very nearly the exact same as ProfileSelected, not used by flagship anyway (for Veteran Status, ultimately unused)
- Chat - redirected to a web URL, Jessica indicated that should just use ExternalLink instead of a special icon
- CircleExternalLink - Superfluous, use ExternalLink
- CirclePhone - Superfluous, use Phone

A second PR will be needed to update Icon accordingly on the components package side.

Nothing really to test. Only nuance really was being sure to add #000 for the fill on what Figma provided to ensure our color overriding works.

Code reviewer validation:

General
- [x] PR is linked to ticket(s)
- [x] PR has changelog label applied if it's to be included in the changelog
- [x] Acceptance criteria:
  - All satisfied or
  - Documented reason for not being performed or
  - Split to separate ticket and ticket is linked by relevant AC(s)
- [x] Above PR sections adequately filled out
- [x] If any breaking changes, in accordance with the pre-1.0.0 versioning guidelines: a CU ticket has been created for the VA Mobile App detailing necessary adjustments with the package version that will be published by this ticket
Code
- [x] Tests are included if appropriate (or split to separate ticket)
- [x] New functions have proper TSDoc annotations

If changes warrant a new version per the versioning guidelines and the PR is approved and ready to merge: