Update spec URLs for CSPViolationReportBody (#16317)
Update spec URLs for CSPViolationReportBody (#16317)

These should all be using the URL for the current spec at
https://w3c.github.io/webappsec-csp rather than the outdated
https://www.w3.org/TR/CSP3 version.
mdn/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data