Fixes issue where Auth emulator sign in with Google only shows default tenant

[aalej]

Description

As mentioned here, "other tenants than the default using the Google Auth Provider are not being listed in the popup sign-in screen". This may be because the link created looks like http://127.0.0.1:9099/emulator/auth/handler?<other_query>&tid=second. The link has a query of tid not tenantId

We are currently looking for the tenantId query.

const tenantId = req.query.tenantId as string | undefined;

Given that we may be using tenantId in the past(or other sdks), keeping both instead of replacing tenantId with tid might be a better option

Scenarios Tested

See https://github.com/aalej/issues_5623-tid for a test case

Using the Auth emulator and Hosting emulator

1. Sign in with "default" tenant
2. Sign out
3. Sign in with "second" tenant
   1. Users from the "default" must not be displayed
4. Sign out
5. Sign in with "default" tenant
   1. Only users from the "default" must be displayed
6. Sign out
7. Sign in with "second" tenant
   1. Only users from the "second" must be displayed

Sample Commands

firebase emulators:start --project <project_id>

[codecov-commenter]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (6b0cb5d) 54.18% compared to head (97d535a) 54.18%.
Report is 1 commits behind head on master.

Files	Patch %	Lines
src/deploy/hosting/convertConfig.ts	0.00%	1 Missing and 1 partial ⚠️
src/emulator/auth/handlers.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6683      +/-   ##
==========================================
- Coverage   54.18%   54.18%   -0.01%     
==========================================
  Files         347      347              
  Lines       24130    24132       +2     
  Branches     4976     4978       +2     
==========================================
  Hits        13075    13075              
- Misses       9855     9856       +1     
- Partials     1200     1201       +1     

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[joehan]

🔥, thanks Alej!