Upgrade Guide Should Note Change in Tail Sampling

The Upgrade Guide at [UPGRADING](https://github.com/coralogix/telemetry-shippers/blob/master/otel-integration/UPGRADING.md) should note that if using tail sampling and upgrading to v0.0.180 (or potentially whenever Coralogix Exporter preset was added), the tail sampling configuration needs to be updated as in [PR 586](https://github.com/coralogix/telemetry-shippers/pull/586).