put credentials in file in action

Author: HartmannVolker

action.yaml

@@ -4,11 +4,12 @@ inputs:
   organisation_id:
     description: 'The Organisation ID, to validate all Databases in your STACKIT organisation.'
     required: true
-  stackit_service_account_key_path:
-    description: "Path to a STACKIT Service Account Key to authenticate against STACKIT API"
+  stackit_service_account_key:
+    description: "STACKIT Service Account Key to authenticate against STACKIT API"
     required: true
 
 runs:
+
   using: 'composite'
   steps:
     - run: echo "INSTALL PYTHON"
@@ -38,12 +39,14 @@ runs:
       run: uv sync
       working-directory: ${{ github.action_path }}
       shell: bash
-    - name: "Test credentials path"
+    - name: "Setup STACKIT Credentials"
       shell: bash
-      run: echo ${{ inputs.stackit_service_account_key_path }}
+      env:
+        STACKIT_SERVICE_ACCOUNT_KEY: ${{ inputs.stackit_service_account_key }}
+      run: echo "$STACKIT_SERVICE_ACCOUNT_KEY" > ${{ github.action_path }}/stackit-credentials.json
     - name: "Validate STACKIT Database ACLs"
       shell: bash
       run:  uv run src/main.py validate-org ${{ inputs.organisation_id }}
       working-directory: ${{ github.action_path }}
       env:
-        STACKIT_SERVICE_ACCOUNT_KEY_PATH: ${{ inputs.stackit_service_account_key_path }}
+        STACKIT_SERVICE_ACCOUNT_KEY_PATH: ${{ github.action_path }}/stackit-credentials.json