Remove linebreaks when Base64 encoding

[roshkins]

base64 adds linebreaks when encoding. use -w 0 to remove them. Throws JSON errors otherwise

[TrevorJTClarke]

@roshkins are you on linux?
I fully feel your pain - adding this change however doesn't work for the people most using this scripting... :(
Therefore, the solution here is to keep this as a referencable fix somewhere, or setup a second set of scripts for linux users.

The bigger problem is actually how the deploy fails for code, which ultimately means linux users cannot do the scripts until near-cli fixes/supports the PR: near/near-cli#938