docs: add OpenSSF Scorecard badge

[gaius-qi]

Description

This pull request includes a small change to the README.md file. The change adds an OpenSSF Scorecard badge to the list of badges in the file.

• README.md: Added the OpenSSF Scorecard badge to the list of badges.

Related Issue

Motivation and Context

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 34.18%. Comparing base (20926e7) to head (a18b16b).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3788      +/-   ##
==========================================
- Coverage   34.20%   34.18%   -0.02%     
==========================================
  Files         337      337              
  Lines       38982    38982              
==========================================
- Hits        13333    13327       -6     
- Misses      24808    24811       +3     
- Partials      841      844       +3     

Flag	Coverage Δ
unittests	34.18% <ø> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

see 2 files with indirect coverage changes