[misc] Fix OpenSSF Scorecard link.

[ditman]

The OpenSSF Scorecard badge/link looks a little bit wonky in the README. This PR fixes it.

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[godofredoc]

Thanks for the fix!

[ditman]

Thanks for the fix!

@godofredoc I wish they had a more human-readable link target than some JSON output!

[godofredoc]

Thanks for the fix!

@godofredoc I wish they had a more human-readable link target than some JSON output!

Let me open a feature request

Thanks for the fix!

@godofredoc I wish they had a more human-readable link target than some JSON output!

Opened a feature request. Worst case scenario they can point us to the location where we can contribute the change.