Fixed toString in Default implementations (#3995)

Author: gosar

core/http-auth-spi/src/main/java/software/amazon/awssdk/http/auth/spi/internal/DefaultHttpSignRequest.java

@@ -62,7 +62,7 @@ public <T> T property(SignerProperty<T> property) {
 
     @Override
     public String toString() {
-        return ToString.builder("DefaultHttpSignRequest")
+        return ToString.builder("HttpSignRequest")
                        .add("payloadType", payloadType)
                        .add("request", request)
                        .add("properties", properties)

core/http-auth-spi/src/main/java/software/amazon/awssdk/http/auth/spi/internal/DefaultSignedHttpRequest.java

@@ -52,10 +52,9 @@ public Optional payload() {
 
     @Override
     public String toString() {
-        return ToString.builder("DefaultSignedHttpRequest")
+        return ToString.builder("SignedHttpRequest")
                        .add("payloadType", payloadType)
                        .add("request", request)
-                       // .add("payload", payload)
                        .build();
     }