React UI login routes

[nhsiehgit]

POC

enable react login page views
point login page to existing login api

[github-actions]

🚨 Warning: This pull request contains Frontend and Backend changes!

It's discouraged to make changes to Sentry's Frontend and Backend in a single pull request. The Frontend and Backend are not atomically deployed. If the changes are interdependent of each other, they must be separated into two pull requests and be made forward or backwards compatible, such that the Backend or Frontend can be safely deployed independently.

Have questions? Please ask in the #discuss-dev-infra channel.

[codecov]

Codecov Report

Merging #52885 (b51ec20) into feature_auth_in (942e278) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@               Coverage Diff                @@
##           feature_auth_in   #52885   +/-   ##
================================================
  Coverage            79.38%   79.39%           
================================================
  Files                 4935     4935           
  Lines               207373   207376    +3     
  Branches             35436    35436           
================================================
+ Hits                164633   164641    +8     
+ Misses               37704    37700    -4     
+ Partials              5036     5035    -1     

Impacted Files	Coverage Δ
src/sentry/api/urls.py	100.00% <ø> (ø)
src/sentry/auth/helper.py	90.86% <ø> (ø)
src/sentry/web/urls.py	92.30% <ø> (ø)
static/app/views/auth/login.tsx	94.59% <ø> (ø)
static/app/views/auth/loginForm.tsx	100.00% <ø> (ø)
static/app/views/dashboards/controls.tsx	94.28% <ø> (ø)
src/sentry/api/endpoints/auth_login.py	100.00% <100.00%> (ø)
src/sentry/web/frontend/auth_login.py	83.07% <100.00%> (+0.08%)	⬆️

... and 1 file with indirect coverage changes

[getsantry]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you remove the label Waiting for: Community, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀