Fix remote E2E token endpoint authentication

[mikaelweave]

Description

Uses the in-process server's configured authority for standard client-credential tokens and requires remote E2E tests to provide TestTokenEndpoint. SMART metadata endpoints remain available to dedicated callers.

Related issues

AB#198445

Testing

dotnet test test/Microsoft.Health.Fhir.R4.Tests.E2E/Microsoft.Health.Fhir.R4.Tests.E2E.csproj -f net10.0 --no-restore -- --filter "FullyQualifiedName~TestFhirServerAuthenticationTests"

FHIR Team Checklist

• Update the title of the PR to be succinct and less than 65 characters
• Add a milestone to the PR for the sprint that it is merged (i.e. add S47)
• Tag the PR with the type of update: Bug, Build, Dependencies, Enhancement, New-Feature or Documentation
• Tag the PR with Open source, Azure API for FHIR (CosmosDB or common code) or Azure Healthcare APIs (SQL or common code) to specify where this change is intended to be released.
• Tag the PR with Schema Version backward compatible or Schema Version backward incompatible or Schema Version unchanged if this adds or updates Sql script which is/is not backward compatible with the code.
• When changing or adding behavior, if your code modifies the system design or changes design assumptions, please create and include an ADR.
• CI is green before merge
• Review squash-merge requirements

Semver Change (docs)

Patch|Skip|Feature|Breaking (reason)

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.66%. Comparing base (318be27) to head (1363f53).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5681      +/-   ##
==========================================
+ Coverage   77.51%   77.66%   +0.15%     
==========================================
  Files        1005     1005              
  Lines       36943    36958      +15     
  Branches     5601     5607       +6     
==========================================
+ Hits        28635    28704      +69     
+ Misses       6948     6895      -53     
+ Partials     1360     1359       -1     

see 20 files with indirect coverage changes

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[mikaelweave]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 5681 in repo microsoft/fhir-server