misc: added cause to unsupported signing algorithm exception (#1036)

Author: 0marperez

runtime/auth/aws-signing-common/api/aws-signing-common.api

@@ -187,6 +187,8 @@ public final class aws/smithy/kotlin/runtime/auth/awssigning/PresignerKt {
 
 public final class aws/smithy/kotlin/runtime/auth/awssigning/UnsupportedSigningAlgorithmException : aws/smithy/kotlin/runtime/ClientException {
 	public fun <init> (Ljava/lang/String;Laws/smithy/kotlin/runtime/auth/awssigning/AwsSigningAlgorithm;)V
+	public fun <init> (Ljava/lang/String;Laws/smithy/kotlin/runtime/auth/awssigning/AwsSigningAlgorithm;Ljava/lang/Throwable;)V
+	public synthetic fun <init> (Ljava/lang/String;Laws/smithy/kotlin/runtime/auth/awssigning/AwsSigningAlgorithm;Ljava/lang/Throwable;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
 	public final fun getSigningAlgorithm ()Laws/smithy/kotlin/runtime/auth/awssigning/AwsSigningAlgorithm;
 }
 

runtime/auth/aws-signing-common/common/src/aws/smithy/kotlin/runtime/auth/awssigning/AwsSigningExceptions.kt

@@ -12,10 +12,25 @@ import aws.smithy.kotlin.runtime.InternalApi
  *
  * See: [AwsSigningAlgorithm], [AwsSigner]
  *
- * @param isSigV4a Whether the unsupported signing algorithm is sigV4a
+ * @param message The message displayed by the exception
+ * @param signingAlgorithm The unsupported signing algorithm
+ * @param cause The cause of the exception
  */
 @InternalApi
 public class UnsupportedSigningAlgorithmException(
     message: String,
     public val signingAlgorithm: AwsSigningAlgorithm,
-) : ClientException(message)
+    cause: Throwable? = null,
+) : ClientException(
+    message,
+    cause,
+) {
+    public constructor(
+        message: String,
+        signingAlgorithm: AwsSigningAlgorithm,
+    ) : this (
+        message,
+        signingAlgorithm,
+        null,
+    )
+}