When running make test repeatedly nixos.qcow2 copied to store

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I noticed that when I run make test repeatedly and there is the nixos.qcow2 lying around in the source directory depending on the file size I eventually get

warning: dumping very large path (> 256 MiB); this may run out of memory
error: out of memory

This is expected as the qcow2 file which may get quite large (depending on virtualization.diskSize and effective size) gets copied to the store, but I wonder if there was something to do about it.

I. e. an option to exclude the file from store ?