fdsn: change NCEDC base URL to https

[megies]

What does this PR do?

change FDSNWS URL for NCEDC to https

Why was it initiated? Any relevant Issues?

fixes #3201

PR Checklist

• Correct base branch selected? master for new features, maintenance_... for bug fixes
• This PR is not directly related to an existing issue (which has no PR yet).
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