[APM] Support sampling discard_on_write_failure configuration in apm integration policy

[isaacaflores2]

Describe the feature:

The apm integration policy configuration UI should support configuring tail sampling discard_on_write_failure. This should be in 9.1 and backported to 8.19.

The copy should follow elastic/docs-content#1453

Part of elastic/apm-server#15330

Describe a specific use case for the feature:

[elasticmachine]

Pinging @elastic/obs-ux-infra_services-team (Team:obs-ux-infra_services)

[carsonip]

This can be implemented together with #219303 as they are similar in nature