Update regression tests

[yifanz0]

Description

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[blueww]

BTW, for the data need prepare:
Following looks a little duplicated (especially for the 2nd, we might don't want to keep 2 big files):

1. testfile_10M , testfile_10240K_0
2. testfile_300M, testfile_300000K_0

| testfile_1K_0 | 1KB |
| testfile_10M | 10M |
| testfile_300M | 300M |
| testfile_2048K | 2048K |
| testfile_10240K_0 | 10240K |
| testfile_300000K_0 | 300000K |

[yifanz0]

@blueww Yes indeed. I'll address the duplicates in the next PR. 300M test file was added only for the blob copy cases to test block to block copy when size is bigger than 256M

[blueww]

@blueww Yes indeed. I'll address the duplicates in the next PR. 300M test file was added only for the blob copy cases to test block to block copy when size is bigger than 256M

Thanks for the reply!
I think we just need to keep 1 test file > 256MB.