Fix AddHeaderOperationTest configuration

Author: tcheeric

phoenixd-test/src/test/java/xyz/tcheeric/phoenixd/operation/impl/AddHeaderOperationTest.java

@@ -1,12 +1,19 @@
 package xyz.tcheeric.phoenixd.operation.impl;
 
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import xyz.tcheeric.phoenixd.common.rest.Operation;
+import xyz.tcheeric.phoenixd.test.TestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 public class AddHeaderOperationTest {
 
+    @BeforeEach
+    void setUpBaseUrl() {
+        TestUtils.setBaseUrl("http://localhost");
+    }
+
     // Ensures adding a header preserves the HTTP method for GET operations
     @Test
     void addHeaderDoesNotChangeMethodForGetOperation() {