add config test and secret for managed identity

src/main/terraform/container_app.tf

@@ -47,6 +47,11 @@ resource "azurerm_container_app" "rtp-activator" {
         secret_name = "identity-client-id"
       }
 
+      env {
+        name        = "AZURE_CLIENT_ID"
+        secret_name = "identity-client-id"
+      }
+
       dynamic "env" {
         for_each = var.rtp_environment_configs
         content {

src/test/java/it/gov/pagopa/rtp/activator/configuration/CosmosDBConfigTest.java

@@ -0,0 +1,44 @@
+package it.gov.pagopa.rtp.activator.configuration;
+
+import com.azure.cosmos.CosmosClientBuilder;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.mockito.Mockito.lenient;
+import static org.mockito.Mockito.verify;
+
+@ExtendWith(MockitoExtension.class)
+class CosmosDBConfigTest {
+
+    @Mock
+    private CosmosPropertiesConfig cosmosPropertiesConfig;
+
+    @InjectMocks
+    private CosmosDBConfig cosmosDBConfig;
+
+    @BeforeEach
+    void setUp() {
+        lenient().when(cosmosPropertiesConfig.getDbName()).thenReturn("test-db");
+        lenient().when(cosmosPropertiesConfig.getEndpoint()).thenReturn("https://test-endpoint:443/");
+    }
+
+    @Test
+    void testGetDatabaseName() {
+        String dbName = cosmosDBConfig.getDatabaseName();
+        assertEquals("test-db", dbName);
+    }
+
+    @Test
+    void testGetCosmosClientBuilder() {
+        CosmosClientBuilder builder = cosmosDBConfig.getCosmosClientBuilder();
+        verify(cosmosPropertiesConfig).getEndpoint();
+        assertNotNull(builder);
+    }
+}