fix: updated broken links (#1630)

Author: garysassano

docs/design_proposal.md

@@ -43,7 +43,7 @@ It's important to clarify that auto-instrumentation is not library instrumentati
 We can have three layers of wrapper on a user's Lambda function: ___Lambda function instrumentation___, ___execution wrapper___ and ___Lambda EXEC Wrapper___. Each one can add new functionality by wrapping the previous one, to further improve user experience.
 ![wrappers](https://user-images.githubusercontent.com/66336933/113330096-3af7b880-92d3-11eb-89bf-580ed8614807.png)
 1. ___Lambda function instrumentation___: 
-Lambda function instrumentation is the first step of OpenTelemetry Lambda support, which is wrapping the Lambda handler function with beginSpan() and endSpan(), adding OpenTelemetry attributes by following [trace](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/faas.md) and [resource](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/resource/semantic_conventions/faas.md) FaaS spec. Java and Python implementations are in place, other languages can refer to the code for them.
+Lambda function instrumentation is the first step of OpenTelemetry Lambda support, which is wrapping the Lambda handler function with beginSpan() and endSpan(), adding OpenTelemetry attributes by following [trace](https://github.com/open-telemetry/semantic-conventions/blob/main/docs/faas/faas-spans.md) and [resource](https://github.com/open-telemetry/semantic-conventions/blob/main/docs/resource/faas.md) FaaS spec. Java and Python implementations are in place, other languages can refer to the code for them.
 2. ___Lambda execution wrapper___: 
 Lambda execution wrapper uses reflection to dynamically decorate the user’s original Lambda function. It can add functionality to a user's existing Lambda function without changing source code, but the user must change the Lambda handler name and add the original handler path as an environment variable. With OpenTelemetry, the decoration can be anything, such as initializing OpenTelemetry components, calling instrumentation, or even implementing instrumentation directly. If desired, a developer can also merge Lambda function instrumentation and Lambda execution wrapper into one wrapper.
 See [Java example](https://github.com/open-telemetry/opentelemetry-java-instrumentation/pull/1471/files) (decorate Lambda instrumentation) and [Python example](https://github.com/open-telemetry/opentelemetry-lambda/blob/main/python/src/otel/otel_sdk/otel_wrapper.py) (initialize OpenTelemetry components for auto-instrumentation).