sentry-manager is used by Keyman Engine for Android and Keyman Engine
for iOS, but not directly by KeymanWeb, nor does it have any
dependencies on /web. So it does not make sense to keep it under /web.
es-bundling is used by sentry-manager and potentially other /common/web
tools in the future, so moving it under /common/tools makes it more
consistent in the future.
This is part of simplifying the web source tree; these changes do not
make significant build performance differences at this time.
Test-bot: skip
