feat: custom user agent CognitoUser changes for UI handoff

[erinleigh90]

Description of changes

• Creates and exports InternalCognitoUser class from /internals scope with added customUserAgentDetails parameter on public API's that result in service calls
• Sends received customUserAgentDetails through to storage service calls
• Send user agent information from Auth to CognitoUser

NOTES

• To see the changes to InternalCognitoUser after moving the changes over from CognitoUser, see this comparison

Description of how you validated changes

yarn tests pass

Checklist

• PR description included
• yarn test passes
• Tests are changed or added

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

[elorzafe]

Overall looks good @erinleigh90

My only concern is InternalCognitoUserPool is not extended by the external one.

[jimblanc]

Same concern as Francisco around the CognitoUserPool extension, but mostly looks good. It might be a good idea to run the integ tests against this branch just due to the volume of changes (too late now, but --no-verify would be useful here to avoid all the prettier changes).

[codecov-commenter]

Codecov Report

Merging #11643 (444ef9b) into main (7365c34) will increase coverage by 0.25%.
The diff coverage is 87.41%.

❗ Your organization is not using the GitHub App Integration. As a result you may experience degraded service beginning May 15th. Please install the Github App Integration for your organization. Read more.

@@            Coverage Diff             @@
##             main   #11643      +/-   ##
==========================================
+ Coverage   83.63%   83.89%   +0.25%     
==========================================
  Files         341      342       +1     
  Lines       21581    20915     -666     
  Branches     4611     4455     -156     
==========================================
- Hits        18050    17547     -503     
+ Misses       3244     3105     -139     
+ Partials      287      263      -24     

Impacted Files	Coverage Δ
packages/amazon-cognito-identity-js/src/Client.js	50.94% <64.28%> (+0.45%)	⬆️
...ages/amazon-cognito-identity-js/src/CognitoUser.js	92.40% <84.61%> (+13.34%)	⬆️
packages/auth/src/Auth.ts	87.84% <87.19%> (+0.25%)	⬆️
packages/auth/src/utils.ts	100.00% <100.00%> (ø)
packages/core/src/Platform/types.ts	100.00% <100.00%> (ø)

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[israx]

User agent changes look good. I really wanna see this metrics.

My only concern is about not changing the public facing API types. Although those changes are not breaking. Proposed return values don't align with return values for v6. I might've missed some APIs but the feedback is for all public API types that are being changed by this PR.

[jimblanc]

Hum appears this didn't trigger a run in circle CI. Probably need to push feature branch to main repo (can keep the PR branch how it is).

[erinleigh90]

Go back through and update jsdocs