docs: add instrumentation quickstart sample

[aabmass]

This is clone of the existing Go and Java samples. I decided to use Fastify because the instrumentation produces nice traces compared to express, it is popular, and has builtin logging with Pino.

I've excluded the sample from the npm workspace which makes it independent from the rest of the repo instead of a "subpackage".

Output of running it in Cloud Shell:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.72%. Comparing base (f9a5c8b) to head (2e272fa).
Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #687   +/-   ##
=======================================
  Coverage   97.72%   97.72%           
=======================================
  Files          18       18           
  Lines         703      703           
  Branches      136      136           
=======================================
  Hits          687      687           
  Misses         16       16           

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[snippet-bot]

Here is the summary of changes.

You are about to add 6 region tags.

• samples/instrumentation-quickstart/Dockerfile:13, tag opentelemetry_instrumentation_agent_dockerfile
• samples/instrumentation-quickstart/src/index.ts:21, tag opentelemetry_instrumentation_create_app
• samples/instrumentation-quickstart/src/index.ts:28, tag opentelemetry_instrumentation_handle_single
• samples/instrumentation-quickstart/src/index.ts:42, tag opentelemetry_instrumentation_handle_multi
• samples/instrumentation-quickstart/src/instrumentation.ts:68, tag opentelemetry_instrumentation_setup_opentelemetry
• samples/instrumentation-quickstart/src/util.ts:28, tag opentelemetry_instrumentation_setup_logging

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[dashpole]

Does this set the http.route?

[aabmass]

Yes it has http.route. It's in metrics too, see the screenshot above.