[chore] add status table to mdatagen (#10898)

not sure why it didn't have one, it's convenient for finding issues w/
mdatagen

Signed-off-by: Alex Boten <[email protected]>

Author: codeboten

cmd/mdatagen/README.md

@@ -1,5 +1,15 @@
 # Metadata Generator
 
+<!-- status autogenerated section -->
+| Status        |           |
+| ------------- |-----------|
+| Stability     | [alpha]: metrics   |
+| Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Acmd%2Fmdatagen%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Acmd%2Fmdatagen) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Acmd%2Fmdatagen%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Acmd%2Fmdatagen) |
+| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@dmitryax](https://www.github.com/dmitryax) |
+
+[alpha]: https://github.com/open-telemetry/opentelemetry-collector#alpha
+<!-- end autogenerated section -->
+
 Every component's documentation should include a brief description of the component and guidance on how to use it.
 There is also some information about the component (or metadata) that should be included to help end-users understand the current state of the component and whether it is right for their use case.
 Examples of this metadata about a component are: