dhi: add redirect (#23841)

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## Description

Add url redirect for in-product link.

## Related issues or tickets

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## Reviews

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- [ ] Editorial review

Signed-off-by: Craig Osterhout <[email protected]>

Author: craig-osterhout

data/redirects.yml

@@ -369,6 +369,8 @@
 # Docker Hardened Images (DHI)
 "/dhi/how-to/customize/":
   - /go/dhi-customization/
+"/dhi/how-to/scan/#scan-a-dhi-using-grype":
+  - /go/dhi-grype/
 
 "/dhi/how-to/customize/#create-an-oci-artifact-image":
   - /go/dhi-customization-artifacts/