Update example-pattern.json (#2447)

The framework showed as CDK but it is meant to be SAM. Corrected.

s3-object-lambda-textract/example-pattern.json

@@ -3,7 +3,7 @@
   "description": "This pattern provides a simple On-demand mechanism of extracting key value pair from document for Intelligent document processing.Example Use case : If an enterprise has a large volume of PDF document and does not want to run a batch job due to the cost of processing of extracting / processing all the document, S3 Ojbect lambda provdies a good mechanism to extract only the OCR document on need basis without major changes to the architecture and in a serverless fashion, optimising cost.",
   "language": "Python",
   "level": "200",
-  "framework": "CDK",
+  "framework": "SAM",
   "introBox": {
     "headline": "How it works",
     "text": [