feat(cli): telemetry sent to endpoint

[kaizencc]

This PR includes the following:

• more robust trace messaging for telemetry success / failure
• use of Funnel class to combine FileSink and EndpointSink
• update integ tests to assert on trace messages that the telemetry sent returns 200 OK
• integ tests of the official endpoint (or the endpoint supplied in TELEMETRY_ENDPOINT)

When merged and released, this PR launches cdk cli telemetry

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[codecov-commenter]

Codecov Report

❌ Patch coverage is 68.75000% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.81%. Comparing base (29a6178) to head (aa6fc7e).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/aws-cdk/lib/cli/io-host/cli-io-host.ts	73.52%	9 Missing ⚠️
...es/aws-cdk/lib/cli/telemetry/sink/endpoint-sink.ts	66.66%	4 Missing ⚠️
...ges/aws-cdk/lib/cli/telemetry/collect-telemetry.ts	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #775      +/-   ##
==========================================
+ Coverage   84.50%   84.81%   +0.30%     
==========================================
  Files          71       72       +1     
  Lines       10445    10469      +24     
  Branches     1344     1350       +6     
==========================================
+ Hits         8827     8879      +52     
+ Misses       1577     1551      -26     
+ Partials       41       39       -2     

Flag	Coverage Δ
suite.unit	84.81% <68.75%> (+0.30%)	⬆️

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