Show OIDC provider name on the OIDC login button

[AllForNothing]

1. Related issue Customize the text of the OIDC login button #13198

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
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[codecov]

Codecov Report

Merging #19581 (903fd48) into main (3f6c029) will decrease coverage by 22.27%.
The diff coverage is 50.00%.

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #19581       +/-   ##
===========================================
- Coverage   67.54%   45.27%   -22.27%     
===========================================
  Files         990      244      -746     
  Lines      109055    13320    -95735     
  Branches     2719     2720        +1     
===========================================
- Hits        73659     6031    -67628     
+ Misses      31429     6989    -24440     
+ Partials     3967      300     -3667     

Flag	Coverage Δ
unittests	45.27% <50.00%> (-22.27%)	⬇️

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Files	Coverage Δ
src/portal/src/app/services/app-config.ts	100.00% <100.00%> (ø)
...ortal/src/app/account/sign-in/sign-in.component.ts	53.33% <0.00%> (-0.52%)	⬇️

... and 748 files with indirect coverage changes