feat: Modify end time of lambda load span to be last cold start node …

[astuyve]

…end time instead of start time of function.

What does this PR do?

Motivation

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Types of Changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• This PR impacts documentation, and it has been updated (or a ticket has been logged)
• This PR's changes are covered by the automated tests
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[codecov-commenter]

Codecov Report

Merging #372 (4c4891d) into main (35295b3) will increase coverage by 0.24%.
The diff coverage is 75.94%.

❗ Current head 4c4891d differs from pull request most recent head f0e253a. Consider uploading reports for the commit f0e253a to get more accurate results

@@            Coverage Diff             @@
##             main     #372      +/-   ##
==========================================
+ Coverage   80.35%   80.59%   +0.24%     
==========================================
  Files          36       38       +2     
  Lines        1761     1902     +141     
  Branches      410      439      +29     
==========================================
+ Hits         1415     1533     +118     
- Misses        294      312      +18     
- Partials       52       57       +5     

Impacted Files	Coverage Δ
src/runtime/user-function.ts	7.69% <ø> (+7.69%)	⬆️
src/trace/listener.ts	64.70% <30.00%> (-3.48%)	⬇️
src/trace/context.ts	80.00% <57.89%> (-8.18%)	⬇️
src/trace/cold-start-tracer.ts	85.71% <85.71%> (ø)
src/runtime/require-tracer.ts	96.96% <96.96%> (ø)
src/index.ts	87.59% <100.00%> (+1.04%)	⬆️
src/runtime/index.ts	100.00% <100.00%> (+100.00%)	⬆️
src/trace/span-inferrer.ts	89.34% <100.00%> (+0.10%)	⬆️

... and 1 file with indirect coverage changes

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[joeyzhao2018]

LGTM