docs(readme): bust OpenSSF badge cache

[adrianbrad]

The OpenSSF Best Practices badge on the repo home page was still rendering as "in progress" after the project reached 100% at bestpractices.dev.

Root cause is Fastly in front of bestpractices.dev: different Fastly PoPs hold different cached copies, and the one GitHub's camo proxy happens to reach is still serving the stale SVG. Direct fetches from other PoPs return the fresh "passing" SVG, and cache-control: no-store on the origin doesn't help once Fastly has cached it.

Fastly keys by URL, so appending a cache-buster (?v=1) creates a new cache entry that has to go to origin, bypassing the stale one. Bump the number the next time this happens.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (949dfd8) to head (06be117).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #65   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            6         6           
  Lines          639       639           
=========================================
  Hits           639       639           

Flag	Coverage Δ
unittests	100.00% <ø> (ø)

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