Upgrade license links to https

[cuviper]

Thanks!

bors r+

[bors[bot]]

Build succeeded:

• Format
• Missing Target
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• Test (1.0.0)
• Test (1.10.0)
• Test (1.15.0)
• Test (1.20.0)
• Test (1.25.0)
• Test (1.30.0)
• Test (1.35.0)
• Test (1.40.0)
• Test (1.45.0)
• Test (1.5.0)
• Test (1.50.0)
• Test (1.55.0)
• Test (1.60.0)
• Test (beta)
• Test (nightly)
• Test (stable)