Update OnPremOAuthFunctions.ps1

[MedElhamm0uti]

Issue:
ACS is no longer the default AuthServer and has been deprecated

Reason:
ACS is no longer the default AuthServer and has been deprecated

Fix:
Updated to check for EvoSts

Validation:
Provide if applicable

[Copilot]

Pull Request Overview

Updates the OnPremOAuthFunctions.ps1 to replace deprecated ACS (Access Control Service) authentication with EvoSts authentication server configuration. This change addresses the deprecation of ACS as the default AuthServer.

• Replaced ACS filter pattern with EvoSts pattern in AuthServer retrieval
• Updated validation patterns for IssuerIdentifier, TokenIssuingEndpoint, and AuthMetadataUrl to match EvoSts endpoints
• Modified error messages to reflect correct EvoSts endpoint formats

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[MedElhamm0uti]

@microsoft-github-policy-service agree

[dpaulson45]

@MarcoLFrancisco to review

[MarcoLFrancisco]

Looks fine, thank you.

[dpaulson45]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[dpaulson45]

@Ghost0s Please address the spelling that failed here:

Use camelCasing or PascalCase

[dpaulson45]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[dpaulson45]

@Ghost0s please follow our contributing guides to get your PR to properly work and pass the build pipeline process:

https://github.com/microsoft/CSS-Exchange/blob/main/CONTRIBUTING.md

Then if you know how, please rebase your branch so there is only 1 commit on the branch you are trying to merge into ours.

[dpaulson45]

@MedElhamm0uti as I provided before, you need to follow the contributing guide to get past the build pipeline. Otherwise, this PR will not merge.

https://github.com/microsoft/CSS-Exchange/blob/main/CONTRIBUTING.md