update ironbank image product name (#8959)

This is required to automate the creation of the ironbank merge requests as the ubireleaser is using this field to compute the apm-server artifact url. For example it is now trying to retrieve https://artifacts.elastic.co/downloads/beats/apm-server-8.4.0-linux-x86_64.tar.gz instead of https://artifacts.elastic.co/downloads/apm-server/apm-server-8.4.0-linux-x86_64.tar.gz

Co-authored-by: Andrew Wilkins <[email protected]>

packaging/ironbank/hardening_manifest.yaml

@@ -35,7 +35,7 @@ labels:
   ## This value can be "opensource" or "commercial"
   mil.dso.ironbank.image.type: "commercial"
   ## Product the image belongs to for grouping multiple images
-  mil.dso.ironbank.product.name: "beats"
+  mil.dso.ironbank.product.name: "apm-server"
 
 # List of resources to make available to the offline build context
 resources: