Use noop instead of embedded for auto/sdk default implementations

[MrAlias]

opentelemetry-go-instrumentation/sdk/trace.go

Line 34 in 3eb8555

type tracerProvider struct{ embedded.TracerProvider }

opentelemetry-go-instrumentation/sdk/trace.go

Lines 47 to 51 in 3eb8555

	type tracer struct {
	embedded.Tracer
	name, schemaURL, version string
	}

opentelemetry-go-instrumentation/sdk/trace.go

Lines 142 to 150 in 3eb8555

	type span struct {
	embedded.Span
	sampled bool
	spanContext trace.SpanContext
	traces *telemetry.Traces
	span *telemetry.Span
	}

The embedded package will cause compilation errors when the implementation of the Go Trace API is not satisfied by an implementation.

Currently this is not an issue because the sdk package fully implements the Trace API. However if ...

0. A new method is added to the Trace API
1. All implementations of the Trace API need to be updated inopentelemetry-go (SDK and global)
2. The global package depends on the auto/sdk implementation, therefore ...
3. The auto/sdk needs to add the missing methods so the global package can compile
4. A new release of the auto/sdk needs to be published
5. The opentelemetry-go global API needs to update their dependency of auto/sdk to the one just release
6. The opentelemetry-go project can make a release with the new Trace API changes

This circular update path can be avoided if the auto/sdk package embeds the noop implementation of the Trace API. The global package can be updated without a new version from auto/sdk needed as the default behavior will be that it compiles and acts as a NoOp. When we are able to develop an implementation of the added method that can be brought into the global API afterwards.