Document Dashboard:Otlp:SuppressUnsecuredTelemetryMessage configuration option (#5197)

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* Document Dashboard:Otlp:SuppressUnsecuredTelemetryMessage configuration option

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* Update docs/fundamentals/dashboard/configuration.md

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docs/fundamentals/dashboard/configuration.md

@@ -117,6 +117,7 @@ Client certificate authentication validates the TLS connection's client certific
 | `Dashboard:Otlp:AuthMode` | `Unsecured` | Can be set to `ApiKey`, `Certificate` or `Unsecured`. `Unsecured` should only be used during local development. It's not recommended when hosting the dashboard publicly or in other settings. |
 | `Dashboard:Otlp:PrimaryApiKey` | `null` | Specifies the primary API key. The API key can be any text, but a value with at least 128 bits of entropy is recommended. This value is required if auth mode is API key. |
 | `Dashboard:Otlp:SecondaryApiKey` | `null` | Specifies the secondary API key. The API key can be any text, but a value with at least 128 bits of entropy is recommended. This value is optional. If a second API key is specified, then the incoming `x-otlp-api-key` header value can match either the primary or secondary key. |
+| `Dashboard:Otlp:SuppressUnsecuredTelemetryMessage` | `false` | Suppresses the unsecured telemetry warning message displayed in the dashboard UI and console when OTLP endpoints are configured with `Unsecured` auth mode. When set to `true`, the warning about unsecured OTLP endpoints won't be displayed. Only suppress this warning in controlled environments where security is managed externally. |
 | `Dashboard:Otlp:AllowedCertificates` | `null` | Specifies a list of allowed client certificates. See [allowed certificates](#allowed-certificates) for more information. |
 | Properties of <xref:Microsoft.AspNetCore.Authentication.Certificate.CertificateAuthenticationOptions> | `null` | Values inside configuration section `Dashboard:Otlp:CertificateAuthOptions:*` are bound to `CertificateAuthenticationOptions`, such as `AllowedCertificateTypes`. |