Chore/sample app readme update (#125)

* Update Sample Code Readme

* F

* Fix typo

Author: MatKuhr

sample-code/spring-app/README.md

@@ -5,15 +5,25 @@
 Sample code to demonstrate the usage of the SAP AI SDK.
 Also used as basis for running E2E tests.
 
-## Build, Run, Deploy Locally
+## Build and Run the Sample App
 
-Build the project with:
+Before you can run the sample app, you need to install the AI SDK into your local Maven repository:
 
-1. `mvn compile`
-2. [Download a service key for your AI Core service instance](../../README.md#set-credentials-as-dedicated-environment-variable)
-3. Create the environment variable `AICORE_SERVICE_KEY`
-4. Run the application with `mvn spring-boot:run`
-5. [See all available endpoints](localhost:8080)
+* Run `mvn install -DskipTests` from the root directory of the repository.
+
+> [!NOTE]  
+> The sample app uses the latest state of the SDK, so make sure to install the SDK after pulling a new version via Git.
+> Alternatively, you check out one of the release tags of the repository, e.g. `git fetch --all --tags && git checkout rel/0.1.0`. 
+
+Next, you'll need to set up credentials for the AI Core service: 
+
+* Follow [these instructions](../../README.md#option-1-set-credentials-as-environment-variable) to configure the credentials via environment variables.
+
+Finally, you can start the sample app:
+ 
+* Run `mvn spring-boot:run` from the sample app directory.
+
+Head to http://localhost:8080 in your browser to see all available endpoints.
 
 ## Run the E2E Test