test: watch integration html and json files

[straker]

Making changes to integration html and json files did not retrigger the npm start build, so you would have to manually quit and restart the process to see changes. The test/integration/index.html file is a generated file so we exclude that file from the watch.

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• Follows the commit message policy, appropriate for next version
• Has documentation updated, a DU ticket, or requires no documentation change
• Includes new tests, or was unnecessary
• Code is reviewed for security by: Jason

[scurker]

👍