feat: enable tree shaking

[pkanal]

Which problem is this PR solving?

Fixes #2855
Original PR: #3087

This PR essentially re-opens #3087 to enable tree shaking for opentelemetry-js packages. This significantly reduces bundle size when using opentelemetry packages in the browser.

Short description of the changes

• Marks sideEffects: false in package.json for most packages to signal to bundlers like Webpack that the module can be tree shaken.
• Setting sideEffects: false should be a safe change here since none of the packages execute code without having a function called. The exception to this is opentelemetry-context-zone which has sideEffects: true because it imports Zone.js which presumably does have some side effects on import.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• Tested locally by modifying package.json & looking at a bundle analyzer
• Tested with the examples in this repo

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated

[codecov]

Codecov Report

Merging #3329 (3a9f748) into main (6ede1ee) will decrease coverage by 0.38%.
The diff coverage is n/a.

❗ Current head 3a9f748 differs from pull request most recent head cd7d823. Consider uploading reports for the commit cd7d823 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3329      +/-   ##
==========================================
- Coverage   93.45%   93.07%   -0.39%     
==========================================
  Files         241      226      -15     
  Lines        7260     6524     -736     
  Branches     1507     1360     -147     
==========================================
- Hits         6785     6072     -713     
+ Misses        475      452      -23     

Impacted Files	Coverage Δ
api/karma.worker.js	0.00% <0.00%> (-100.00%)	⬇️
packages/opentelemetry-resources/karma.worker.js	0.00% <0.00%> (-100.00%)	⬇️
...kages/opentelemetry-sdk-trace-base/karma.worker.js	0.00% <0.00%> (-100.00%)	⬇️
...lemetry-resources/src/detectors/BrowserDetector.ts	53.33% <0.00%> (-46.67%)	⬇️
...lemetry-resources/src/detectors/ProcessDetector.ts	95.45% <0.00%> (-4.55%)	⬇️
...ckages/opentelemetry-sdk-trace-web/karma.worker.js
...s/opentelemetry-instrumentation-fetch/src/fetch.ts
...emetry-instrumentation-xml-http-request/src/xhr.ts
...ation-xml-http-request/src/enums/AttributeNames.ts
...es/opentelemetry-context-zone-peer-dep/src/util.ts
... and 10 more

[legendecas]

@vmarchaud has your concern been resolved?

[vmarchaud]

@vmarchaud has your concern been resolved?

Sorry i didn't see your answer

[dyladan]

Test failure appears to be #3344