CI VMs are too small for desired acceptance tests

[j-hartley]

Standard (free) github Action VMs do not have sufficient disk space to run the full system acceptance tests.

We would like to test with 1 million files and, separatly a 250GB file, which are representative of typical Filecoin stored datasets. However github Action virtual machines only have 14GB of disk

For now we have implemented automated CI tests with each of 1000 files and 36MB files. The larger acceptance tests shall be performed manually as part of initial project acceptance testing.