Make Steeltoe Metrics extensions play nice with Otel

[hananiel]

Final version:

1. Calling AddAllActuators will do everything for you including configuring OpenTelemetry metrics and Otels methods do not have to be invoked.
2. But if you call Otel's extension method and provide custom configuration and then call AddOpenTelemetryMetricsForSteeltoe via AddAllActuators, a warning is written to Console and Steeltoe configuration will be ignored. Calling metrics, prometheus will not produce any metrics, and a warning will be logged.
3. If you call Steeltoe AddAllActuators first, and then call Otel via AddOpenTelemetryMetrics, Otel configuration will take precedence and Steeltoe configuration will be ignored. There will be no warning, because we don't have an opportunity to detect this. Calling metrics, prometheus will not produce any metrics, and a warning will be logged.
4. There is now an option to Configure steeltoe metrics with any custom Otel configuration:

 var host = hostBuilder
                .ConfigureServices(services => services.AddOpenTelemetryMetrics(
                    builder => builder
                    .ConfigureSteeltoeMetrics()
                    .AddConsoleExporter()))
                .AddAllActuators()
                .Start();

This will start logging Steeltoe Observer metrics to console and prometheus and metrics endpoints will work correctly.

[TimHess]

/azp run Steeltoe.All

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