Added Test for CatalogTable.as_json #1319

[KimFarida]

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• Have you followed the guidelines in our Contribution Guide
• Have you written new tests for your core changes, as applicable?
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Description

This PR introduces a new test suite for the as_json method of the CatalogTable class, ensuring accurate conversion of catalog data to JSON format. The tests verify data integrity and structure, validating that the output matches the expected format and contents.

Changes to be made

• Added a new directory inputs/test_catalog containing test_catalog.json, which serves as sample input data for testing.
  Implemented a test function, test_as_json, to:
  • Confirm the output of as_json is a valid JSON string.
  • Validate the parsed result maintains the correct structure and data integrity.
  • Handle scenarios with standard and empty catalog data, ensuring appropriate output for both cases.

Status

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To do

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Is this pull request related to any open issue? If yes, replace issueID below with the issue ID

Related to #1319