Recreate the manual testing of share encoding

[evan-forbes]

Why is this test commented?

Originally posted by @sweexordious in #627 (comment)

When moving share encoding and decoding logic to the app, we had to comment out a test because it was designed around some tendermint logic, like creating votes and using methods instead of functions to encode shares. We should recreate this test by changing those requirements.

[evan-forbes]

we have since added quite a few manual tests, and I'm not sure of the value that we would get from this anymore. I guess the manual tests would act as a forcing function to notify reviewers if anything changes the encoding, but that's about it.

Leaving this as a stretch issue for the epic, but I am also okay with closing this as unplanned. Will defer to @rootulp

[rootulp]

This issue refers to the TestMakeShares test which was commented out and eventually removed. It appears to have tested

// 			got := tt.args.data.SplitIntoShares()

which no longer exists but it resembles

celestia-app/pkg/shares/share_splitting.go

Line 25 in 0b85a0f

func Split(data coretypes.Data, useShareIndexes bool) ([]Share, error) {

which doesn't have unit tests so I think we can update this issue to add unit tests to that function.

[rootulp]

That file has been migrated to the go-square repo: https://github.com/celestiaorg/go-square/blob/main/shares/share_splitting.go

SplitTxs has tests but SplitBlobs doesn't: https://github.com/celestiaorg/go-square/blob/main/shares/share_splitting_test.go