tests/extmod: Update littlefs test output to match new library version.
tests/extmod: Update littlefs test output to match new library version.

The amount of free space on the VfsLfs2 filesystem after creating a large
file is reduced by 2 blocks in this test.

pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython