chore: do not add newlines to object data

[achingbrain]

For consistency with go-ipfs we should not add newlines to the output of ipfs object data.

go:

$ echo 'Hello' | ipfs files write --create /hello.txt
$ ipfs files ls / -l | grep hello.txt
hello.txt	QmcnK4wpoB6ozwZ7Siye8wyVTHYKNNoNvapPMLuCYUrHK2	6
$ ipfs object data QmcnK4wpoB6ozwZ7Siye8wyVTHYKNNoNvapPMLuCYUrHK2 | xxd
00000000: 0802 1806 2006                           .... .

js without this PR (with experimental mfs support) - note the extra 0a at the end:

$ echo 'Hello' | JSipfs files write --create /hello.txt
$ jsipfs files ls / -l | grep hello.txt
hello.txt	QmZo8WtosAnHDHXWCvih3xJsiENgdaKBmdx4gKnYmRtSUu	6 
$ jsipfs object data QmZo8WtosAnHDHXWCvih3xJsiENgdaKBmdx4gKnYmRtSUu | xxd
00000000: 0802 1806 2006 0a                        .... ..

js with this PR:

$ echo 'Hello' | JSipfs files write --create /hello.txt
$ jsipfs files ls / -l | grep hello.txt
hello.txt	QmZo8WtosAnHDHXWCvih3xJsiENgdaKBmdx4gKnYmRtSUu	6 
$ jsipfs object data QmZo8WtosAnHDHXWCvih3xJsiENgdaKBmdx4gKnYmRtSUu | xxd
00000000: 0802 1806 2006                           .... .

You may notice that the CIDs are different between go and js although the content is identical - this is because they structure the DAG differently for small files - js uses a single node if the data will fit in one node, go always creates one child that holds the data but this can be addressed in a separate PR.

[daviddias]

remove .only before merging

[fsdiogo]

Good catch 👍

[daviddias]

Please rebase master onto this branch for green CI

[alanshaw]

@diasdavid can you please approve this PR so it can be merged 🙏

[daviddias]

@alanshaw approved. Please add an API change to #1320