Remove `< Browse sites` from sidebar #85401

Job	Run time
Determine tests matrix	1m 4s
E2E: Build jetpack-core	4m 4s
Jetpack connection e2e tests	5m 4s
Jetpack pre-connection e2e tests	2m 26s
Jetpack post-connection e2e tests	4m 25s
Slack notification	1m 1s
Test report	8s
	18m 12s

Provide feedback