Bump cross-spawn from 7.0.3 to 7.0.6 in /ui-tests (jupyterlab#1379)

Bumps [cross-spawn](https://github.com/moxystudio/node-cross-spawn) from 7.0.3 to 7.0.6.
- [Changelog](https://github.com/moxystudio/node-cross-spawn/blob/master/CHANGELOG.md)
- [Commits](moxystudio/node-cross-spawn@v7.0.3...v7.0.6)

---
updated-dependencies:
- dependency-name: cross-spawn
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

ui-tests/yarn.lock

@@ -2043,13 +2043,13 @@ __metadata:
   linkType: hard
 
 "cross-spawn@npm:^7.0.0":
-  version: 7.0.3
-  resolution: "cross-spawn@npm:7.0.3"
+  version: 7.0.6
+  resolution: "cross-spawn@npm:7.0.6"
   dependencies:
     path-key: "npm:^3.1.0"
     shebang-command: "npm:^2.0.0"
     which: "npm:^2.0.1"
-  checksum: 8/671cc7c7288c3a8406f3c69a3ae2fc85555c04169e9d611def9a675635472614f1c0ed0ef80955d5b6d4e724f6ced67f0ad1bb006c2ea643488fcfef994d7f52
+  checksum: 10c0/053ea8b2135caff68a9e81470e845613e374e7309a47731e81639de3eaeb90c3d01af0e0b44d2ab9d50b43467223b88567dfeb3262db942dc063b9976718ffc1
   languageName: node
   linkType: hard