Use HTTPS for links to EPL-2.0 in license headers

[Godin]

Nowadays License Header template in Eclipse Project Handbook uses HTTPS - see https://www.eclipse.org/projects/handbook/#ip-copyright-headers

This was not the case in April 2025 and thus earlier too when we switched to 2.0 in #26

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find . -type f -not -path "./.git/*" -exec grep -I -q . {} \; -print -exec sed -i '' -e 's=http://www.eclipse.org/legal/epl-2.0=https://www.eclipse.org/legal/epl-2.0=g' {} \;