Replacing http:// with https://

[dfa1]

What problem does this pull request solve?

Switching to HTTPS for most URLs

Please provide any additional information below.

NOTE

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[github-actions]

Looks good. No mutations were possible for these changes.
Mutation testing report generated by PITest - https://pitest.org - if there are surviving mutants, please check the line comments under 'Files changed', or the full report under the 'CI / pitest' check below this comment.

[github-actions]

Looks good. No mutations were possible for these changes.
Mutation testing report generated by PITest - https://pitest.org - if there are surviving mutants, please check the line comments under 'Files changed', or the full report under the 'CI / pitest' check below this comment.

[jqno]

Sorry for the late reply.
Thanks for this PR! I never thought to do this, especially the ones in the Java code itself...