F/support table filter expr

[srjonemed]

Description of change

Extending full_table replication mode to optionally support Filtering. Dynamodb already supports the "FilterExpression", and "ExpressionAttributeValues" options as part of the scan table command. This PR passes through these options from Metadata (catalog) over to client.scan() via scan_params.

Manual QA steps

• Step1: Update the catalog.json metadata section
  Here's an example table definition from catalog.json updated to have the FilterExpression
  {"table_name": "my-table-name", "stream": "my-table-name", "tap_stream_id": "my-table-name", "metadata": [{"breadcrumb": [], "metadata": {"table-key-properties": ["model_name", "created_date"], "row-count": 562522, "selected": true, "replication-method": "FULL_TABLE", "FilterExpression": "begins_with(created_date, :dt)", "ExpressionAttributeValues": "{\":dt\":{\"S\":\"2020-03-27\"}}"}}], "schema": {"type": "object"}}

• Step2: Run the tap using the modified catalog.json
  bin/tap-dynamodb --config tap-dynamodb/config.json --catalog tap-dynamodb/catalog.json

• Step3: Expected result, the source table "my-table-name" is scanned based on attribute "created_date" values beginning with "2020-03-27"

Risks

Rollback steps

• revert this branch

[cmerrick]

Hi @srjonemed, thanks for your contribution!

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[cmerrick]

You did it @srjonemed!

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