add changeset

Author: sissbruecker

.changeset/perfect-lies-rush.md

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+---
+'@web/test-runner-saucelabs': minor
+---
+
+Bump saucelabs to 9.0.0 and update test-runner-saucelabs to changes in the new version.
+The new version contains breaking changes, see the migration guide for more information: https://docs.saucelabs.com/secure-connections/sauce-connect-5/migrating/.