fix: update readme (test release (#93)

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## Related Issues


Thanks for contributing!

README.md

@@ -2,5 +2,16 @@
 Shared modules for Spacecat Services
 
 ## Modules
+- `spacecat-shared-data-access` - Models and data access layer
 - `spacecat-shared-dynamodb` - DynamoDB client for basic access
 - `spacecat-shared-utils` - Utility functions
+
+## Installation
+```bash
+$ npm install @adobe/spacecat-shared-data-access
+$ npm install @adobe/spacecat-shared-dynamodb
+$ npm install @adobe/spacecat-shared-utils
+```
+
+## Usage
+See the [API documentation](docs/API.md).