Bump tar and elm-format

Removes [tar](https://github.com/isaacs/node-tar). It's no longer used after updating ancestor dependency [elm-format](https://github.com/avh4/elm-format). These dependencies need to be updated together.


Removes `tar`

Updates `elm-format` from 0.8.5 to 0.8.8
- [Release notes](https://github.com/avh4/elm-format/releases)
- [Changelog](https://github.com/avh4/elm-format/blob/0.8.8/CHANGELOG.md)
- [Commits](avh4/elm-format@0.8.5...0.8.8)

---
updated-dependencies:
- dependency-name: tar
  dependency-version:
  dependency-type: indirect
- dependency-name: elm-format
  dependency-version: 0.8.8
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -42,7 +42,7 @@
   "dependencies": {
     "elm": "0.19.1-5",
     "elm-doc-preview": "^5.0.5",
-    "elm-format": "^0.8.2",
+    "elm-format": "^0.8.8",
     "elm-review": "^2.10.2",
     "elm-test": "0.19.1-revision12",
     "elm-verify-examples": "^5.2.0",