Fix execution of large version bubble composite images (#36373)

Fix execution of large version bubble composite images (#36373)

Large-bubble composite images are special in having more entries
in the manifest metadata than in the component assembly table:
When the build starts, all component assemblies get hard-injected
into the manifest metadata and subsequently we lazily add those
additional reference assemblies (within the same version bubble)
as we need for encoding signatures.

Thanks

Tomas