Instrument akka-http bindAndHandle

[laurit]

Resolves #8143
Resolves #6081
Resolves #5137
Using the same approach as in #6243 and as used by DataDog. Unlike in #6243 this pr does not attempt to prevent leaking scopes into actors but rather instruments the actor to reset context to get rid of the leaked scopes (DataDog does the same).

[trask]

👍

[zackman0010]

@laurit It's good to see that someone else is picking this up, since our legal team never would respond to our emails to sign our CLA.
Disregard the struck text, I looked back at our old merge and saw we did the same thing.. That's what happens when you come back to a project after almost a year and try to talk like you know what you're talking about 😅. Although is there any particular reason you code to accept the scope leakage instead of using a PinnedDispatcher like our original MR did? And if we later get the CLA signed, would you have any objections to us reintroducing the PinnedDispatcher to get rid of the scope leakage?
However, I do have a potential concern. The way you've maintained the scopes is through a queue, which assumes the requests and responses will arrive in the same order. But unfortunately Akka doesn't work that way, the responses may leave in a different order than the requests arrived. If you make request A followed by request B but B finishes first, then B arriving back in the AkkaFlowWrapper would pull A's scope off the queue instead. This is the reason our solution ended up using the PinnedDispatcher to prevent scope leakage.

For what it's worth, we're attempting to restart the process with our legal team again so that we can help contribute. Our company is making a big push to move off AppDynamics and other paid services by replacing them with open source alternatives such as OpenTelemetry, so we'd love to be able to contribute fixes.

[laurit]

@zackman0010 For me it is too hard to understand the ramifications of using PinnedDispatcher instead of what is used by default. This is why I chose to let the scope leak and deal with that.