chore: remove styled-components and related code from package files (#61709)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: francinelucca

.github/dependabot.yml

@@ -18,8 +18,6 @@ updates:
     ignore:
       # Because this is so dependent on the remote server we use
       - dependency-name: '@elastic/elasticsearch'
-      # Because whatever we have needs to match what @primer/react also uses
-      - dependency-name: 'styled-components'
       - dependency-name: '*'
         update-types:
           ['version-update:semver-patch', 'version-update:semver-minor']