feat(opentelemetry-sampler-aws-xray): add x-ray remote sampler

[carolabadeer]

Which problem is this PR solving?

• This PR adds a new feature to support centralized/remote sampling in AWS X-Ray. This PR is the first among a series of PRs to implement this feature.

Short description of the changes

• Created a new opentelemetry-sampler-aws-xray package to vend this new component since all AWS components in this repo have been split into their own packages.
• Added the AWSXRayRemoteSampler skeleton class, which will have more logic added in the next PR for matching sampling rules.
  • The shouldSample and toString methods have been implemented, but currently return values that will be updated in coming PRs.
  • The AWSXRayRemoteSampler allows for specifying a polling interval and will fetch sampling rules periodically using that interval using the setInterval function.
• The remote-sampler.types.ts file houses all the interfaces / data models that the X-Ray remote sampler uses. All interfaces will be defined in this file and additional interfaces will also be added there.

[willarmiros]

Mostly minor comments, skeleton looks good though!

[blumamir]

Thanks for contributing this component.
Left comments on the PR, please write if anything is not clear.

Please also add yourself as the component owner in this file. This means you will be responsible to review and maintain this component in the future.

[codecov]

Codecov Report

Merging #1443 (0dc2a36) into main (4eb405e) will decrease coverage by 0.06%.
The diff coverage is 94.87%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1443      +/-   ##
==========================================
- Coverage   96.13%   96.08%   -0.06%     
==========================================
  Files          14       15       +1     
  Lines         906      945      +39     
  Branches      197      203       +6     
==========================================
+ Hits          871      908      +37     
- Misses         35       37       +2     

Impacted Files	Coverage Δ
...entelemetry-sampler-aws-xray/src/remote-sampler.ts	94.87% <94.87%> (ø)

[Flarna]

maybe add some sanity check to avoid negative or terrible small values?

[Flarna]

Does this work reliable in AWS lambda where the runtime simply freezes the process once the handler returned?

[carolabadeer]

AWS Lambda does not support remote sampling, it uses a fixed sampling rate

[Flarna]

Maybe mention this incompatibility in the readme.
At least from the package name it's not clear to me that AWS lambda is unsupported.

[carolabadeer]

Sure! I added a note in the readme to indicate that AWS Lambda does not support remote sampling

[pichlermarc]

I'm not too familiar with sampling, but the skeleton looks good. 🙂
Looking forward to the follow-up PRs.