Add OSSF Best Practices badge

[artemgavrilov]

PMM-7

This PR adds OSSF best practices badge, I filled some fields in the form here: https://www.bestpractices.dev/en/projects/9702
But it still requires some efforts to complete it

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 42.07%. Comparing base (c9a00bc) to head (eec6d8f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3303      +/-   ##
==========================================
- Coverage   42.07%   42.07%   -0.01%     
==========================================
  Files         399      399              
  Lines       50722    50722              
==========================================
- Hits        21341    21339       -2     
- Misses      27371    27372       +1     
- Partials     2010     2011       +1     

Flag	Coverage Δ
admin	11.59% <ø> (ø)
agent	51.98% <ø> (ø)
managed	42.78% <ø> (-0.01%)	⬇️
vmproxy	68.57% <ø> (ø)

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