Set idle socket keepalive time to 4 seconds

[ghoshkaj]

The tinylicious tests infrequently but consistently fail with 502 error code. A possible cause might be because the node (Axios) server socket timeout is 15s, whereas the underlying socket timeout default timeout is 5s. This PR switches to using agentkeepalive package that forces the Node server to understand and close connections idle sockets after 4 seconds so that Node doesn't try to use an already closed socket.

Implementing this fix on both client calls and internal server calls, since both locations can have this problem.

[curtisman]

I don't think timeout is related to keepAlive, it is just a general timeout for the socket.
I beileve you will need to use agentkeepalive package, which has an extra option to specify freeSocketTimeout. I don't think we need to specify a number, as it is already default to 4000ms.

[ghoshkaj]

Sadly, I don't think this is fixing the error after all. 4/10 runs failed:
Failed runs:

Pipelines - Run 87750 (azure.com)
Pipelines - Run 87771 (azure.com)
Pipelines - Run 87772 (azure.com)
Pipelines - Run 87776 (azure.com)

[github-actions]

🔗 Found some broken links! 💔

Run a link check locally to find them. See
https://github.com/microsoft/FluidFramework/wiki/Checking-for-broken-links-in-the-documentation for more information.

linkcheck output

> fluidframework-docs@0.25.0 linkcheck /home/runner/work/FluidFramework/FluidFramework/docs
> npm run linkcheck:fast -- --external


> fluidframework-docs@0.25.0 linkcheck:fast /home/runner/work/FluidFramework/FluidFramework/docs
> linkcheck http://localhost:1313 --skip-file skipped-urls.txt "--external"

Crawling...

http://localhost:1313/css/style.min.f22f6c22fcc37a0d857a17c9c1202a67c28deef90cc26a52b7539b903f623331.css
- (1:1184) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.eot (HTTP 503)
- (1:1272) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.eot? (HTTP 503)
- (1:1740) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.svg (HTTP 503)

http://localhost:1313/docs/apis/core-interfaces/ifluidcodedetailscomparer
- (873:360) 'Array.sort' => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#Description (HTTP 200 but missing anchor)
- (877:168) 'https://..' => https://github.com/npm/node-semver#usage (HTTP 200 but missing anchor)
- (885:25) 'Array.sort' => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#Description (HTTP 200 but missing anchor)
- (914:25) 'https://..' => https://github.com/npm/node-semver#usage (HTTP 200 but missing anchor)

http://localhost:1313/docs/apis/core-interfaces/ifluidcodedetailscomparer/
- (873:360) 'Array.sort' => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#Description (HTTP 200 but missing anchor)
- (877:168) 'https://..' => https://github.com/npm/node-semver#usage (HTTP 200 but missing anchor)
- (885:25) 'Array.sort' => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#Description (HTTP 200 but missing anchor)
- (914:25) 'https://..' => https://github.com/npm/node-semver#usage (HTTP 200 but missing anchor)


Summary of most serious issues:

http://localhost:1313/css/style.min.f22f6c22fcc37a0d857a17c9c1202a67c28deef90cc26a52b7539b903f623331.css
- (1:1184) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.eot (HTTP 503)
- (1:1272) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.eot? (HTTP 503)
- (1:1740) url(...) => https://c.s-microsoft.com/static/fonts/segoe-ui/west-european/semilight/latest.svg (HTTP 503)


Stats:
  121031 links
    1316 destination URLs
       1 URLs ignored
       8 warnings
       3 errors