doc: Fix broken link in DJL SageMaker docs (aws#3831)

Author: siddvenk

doc/frameworks/djl/using_djl.rst

@@ -213,7 +213,7 @@ For more information about DJL Serving, see the `DJL Serving documentation. <htt
 SageMaker DJL Classes
 ***********************
 
-For information about the different DJL Serving related classes in the SageMaker Python SDK, see https://sagemaker.readthedocs.io/en/stable/sagemaker.djl_inference.html.
+For information about the different DJL Serving related classes in the SageMaker Python SDK, see https://sagemaker.readthedocs.io/en/stable/frameworks/djl/sagemaker.djl_inference.html.
 
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 SageMaker DJL Serving Containers