[docs] Add status header for sigv4auth (open-telemetry#12155)

extension/sigv4authextension/README.md

@@ -1,5 +1,10 @@
 # Authenticator - Sigv4
 
+| Status | |
+| ------------------------ |----------------------|
+| Stability | [beta] |
+| Distributions | [contrib] |
+
 This extension provides Sigv4 authentication for making requests to AWS services. For more information on the Sigv4 process, please look [here](https://docs.aws.amazon.com/general/latest/gr/signature-version-4.html).
 
 ## Configuration
@@ -46,3 +51,6 @@ service:
 ## Notes
 
 * The collector must have valid AWS credentials as used by the [AWS SDK for Go](https://aws.github.io/aws-sdk-go-v2/docs/configuring-sdk/#specifying-credentials)
+
+[beta]:https://github.com/open-telemetry/opentelemetry-collector#beta
+[contrib]:https://github.com/open-telemetry/opentelemetry-collector-releases/tree/main/distributions/otelcol-contrib