Update README.md (slsa-framework#636)

Signed-off-by: laurentsimon <64505099+laurentsimon@users.noreply.github.com>

internal/builders/generic/README.md

@@ -15,7 +15,6 @@ project simply generates provenance as a separate step in an existing workflow.
 
 ---
 
-- [Project Status](#project-status)
 - [Benefits of Provenance](#benefits-of-provenance)
 - [Generating Provenance](#generating-provenance)
   - [Getting Started](#getting-started)
@@ -33,12 +32,6 @@ project simply generates provenance as a separate step in an existing workflow.
 
 ---
 
-## Project Status
-
-This project is currently under active development. The API could change while
-approaching an initial release. You can track progress towards General
-Availability via [this milestone](https://github.com/slsa-framework/slsa-github-generator/milestone/2).
-
 ## Benefits of Provenance
 
 Using the generic workflow will generate a non-forgeable attestation to the