docs(registry.yaml): add nonce

[leogr]

What type of PR is this?

Uncomment one (or more) /kind <> lines:

/kind bug

/kind cleanup

/kind design

/kind documentation

/kind failing-test

/kind feature

Any specific area of the project related to this PR?

Uncomment one (or more) /area <> lines:

/area plugins

/area registry

/area build

/area documentation

What this PR does / why we need it:

# This nonce is used to force a CI job to re-run when no other meaningful changes are made.
# For example, this can be used to update the artifact index: https://github.com/falcosecurity/falcoctl/blob/gh-pages/index.yaml
# To trigger the job manually, update the number below (e.g., by replacing it with the current Unix timestamp).
# It does not need to be secure or unique beyond being different from the previous value.
# Example: `date +%s` on Unix-like systems will generate a suitable value.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:
/hold

I will unhold when needed.

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: leogr

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• OWNERS [leogr]

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[poiana]

Issues go stale after 90d of inactivity.

Mark the issue as fresh with /remove-lifecycle stale.

Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Provide feedback via https://github.com/falcosecurity/community.

/lifecycle stale

[poiana]

Stale issues rot after 30d of inactivity.

Mark the issue as fresh with /remove-lifecycle rotten.

Rotten issues close after an additional 30d of inactivity.

If this issue is safe to close now please do so with /close.

Provide feedback via https://github.com/falcosecurity/community.

/lifecycle rotten

[leogr]

/remove-lifecycle rotten