[BUG] Wrong measurement of SerializeAsync and DeserializeAsync diagnostics

[sp-jcberleur]

What is the bug?

SerializeAsync and DeserializeAsync only measure the time it takes to return the Task, not the execution time because they don't await in the using block

What is the expected behavior?

Serialize and Deserialze spans should include the execution time even in async mode

[krisfreedain]

Catch All Triage - 1 2