Remove jackson from explicit depndencies. Add more tests

Author: alextwoods

services/signin/pom.xml

@@ -56,10 +56,5 @@
             <artifactId>http-auth-aws</artifactId>
             <version>${awsjavasdk.version}</version>
         </dependency>
-        <dependency>
-            <groupId>software.amazon.awssdk</groupId>
-            <artifactId>third-party-jackson-core</artifactId>
-            <version>${awsjavasdk.version}</version>
-        </dependency>
     </dependencies>
 </project>

services/signin/src/test/java/software/amazon/awssdk/services/signin/auth/internal/DpopHeaderGeneratorTest.java

@@ -17,6 +17,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -37,11 +38,12 @@
 import software.amazon.awssdk.services.signin.internal.DpopHeaderGenerator;
 
 public class DpopHeaderGeneratorTest {
-    private static final String VALID_TEST_PEM = "-----BEGIN EC PRIVATE KEY-----\n"
-                                                 + "MHcCAQEEICeY73qhQO/3o1QnrL5Nu3HMDB9h3kVW6imRdcHks0tboAoGCCqGSM49"
-                                                 + "AwEHoUQDQgAEbefyxjd/UlGwAPF6hy0k4yCW7dSghc6yPd4To0sBqX0tPS/aoLrl"
-                                                 + "QnPjfDslgD29p4+Pgwxj1s8cFHVeDKdKTQ==\n"
-                                                 + "-----END EC PRIVATE KEY-----";
+    private static final String VALID_TEST_PEM =
+        "-----BEGIN EC PRIVATE KEY-----\n"
+        + "MHcCAQEEICeY73qhQO/3o1QnrL5Nu3HMDB9h3kVW6imRdcHks0tboAoGCCqGSM49"
+        + "AwEHoUQDQgAEbefyxjd/UlGwAPF6hy0k4yCW7dSghc6yPd4To0sBqX0tPS/aoLrl"
+        + "QnPjfDslgD29p4+Pgwxj1s8cFHVeDKdKTQ==\n"
+        + "-----END EC PRIVATE KEY-----";
     private static final ObjectMapper MAPPER = new ObjectMapper();
 
     @Test
@@ -84,6 +86,15 @@ public void testGenerateAndVerifyDPoPHeader() throws Exception {
         assertTrue(verified, "DPoP ES256 signature should verify correctly");
     }
 
+    @Test
+    public void invalidKey_raisesException() {
+        assertThrows(IllegalArgumentException.class, () -> {
+            DpopHeaderGenerator.generateDPoPProofHeader(
+                "INVALID-KEY", "https://example.com",
+                Instant.now().getEpochSecond(), UUID.randomUUID().toString());
+        });
+    }
+
     /**
      * Verifies an ES256 signature given base64url-encoded JWT parts and the JWK public key.
      */