Remove redundant auth error content

[chlowell]

ChainedTokenCredential errors

Before

DefaultAzureCredential authentication failed. failed to acquire a token.
Attempted credentials:
        EnvironmentCredential: missing environment variable AZURE_TENANT_ID
        WorkloadIdentityCredential: no client ID specified. Check pod configuration or set ClientID in the options
        ManagedIdentityCredential authentication failed. ManagedIdentityCredential authentication failed. authentication failed
GET http://169.254.169.254/metadata/identity/oauth2/token
--------------------------------------------------------------------------------
RESPONSE 401 Unauthorized
--------------------------------------------------------------------------------
{
  "error": "unauthorized"
}
--------------------------------------------------------------------------------
To troubleshoot, visit https://aka.ms/azsdk/go/identity/troubleshoot#managed-id
GET http://169.254.169.254/metadata/identity/oauth2/token
--------------------------------------------------------------------------------
RESPONSE 401 Unauthorized
--------------------------------------------------------------------------------
{
  "error": "unauthorized"
}
--------------------------------------------------------------------------------
To troubleshoot, visit https://aka.ms/azsdk/go/identity/troubleshoot#managed-id
GET http://169.254.169.254/metadata/identity/oauth2/token
--------------------------------------------------------------------------------
RESPONSE 401 Unauthorized
--------------------------------------------------------------------------------
{
  "error": "unauthorized"
}
--------------------------------------------------------------------------------

After

DefaultAzureCredential: failed to acquire a token.
Attempted credentials:
        EnvironmentCredential: missing environment variable AZURE_TENANT_ID
        WorkloadIdentityCredential: no client ID specified. Check pod configuration or set ClientID in the options
        ManagedIdentityCredential authentication failed.
                GET http://169.254.169.254/metadata/identity/oauth2/token
                --------------------------------------------------------------------------------
                RESPONSE 401 Unauthorized
                --------------------------------------------------------------------------------
                {
                  "error": "unauthorized"
                }
                --------------------------------------------------------------------------------
                To troubleshoot, visit https://aka.ms/azsdk/go/identity/troubleshoot#managed-id

Lone credentials built on MSAL

Before

ClientSecretCredential authentication failed. FromClientSecret(): http call(https://login.microsoftonline.com/fake-tenant/oauth2/v2.0/token)(POST) error: reply status code was 418:
no tokens here
Request information not available
--------------------------------------------------------------------------------
RESPONSE I'm a teapot
--------------------------------------------------------------------------------
no tokens here
--------------------------------------------------------------------------------
To troubleshoot, visit https://aka.ms/azsdk/go/identity/troubleshoot#client-secret

After

ClientSecretCredential authentication failed.
Request information not available
--------------------------------------------------------------------------------
RESPONSE 418: I'm a teapot
--------------------------------------------------------------------------------
no tokens here
--------------------------------------------------------------------------------
To troubleshoot, visit https://aka.ms/azsdk/go/identity/troubleshoot#client-secret

[jhendrixMSFT]

Looks way better!