SEC-283 - Preserve whitespace formatting for comments in property files

[arvindth]

Changes:

• Update to use the confluent fork of the underlying go library for property file parsing & writing
• Remove previous workaround to add/remove a final dummy key/value pair to preserve trailing comments in the input property files. This is now handled natively by the updated library.
• Update the call to read/write property files to use the new preserveFormatting option.

Note:
Upstream PR - magiconair/properties#38

• If it gets accepted upstream, cli should be reverted to point back to the upstream library and the confluentinc/properties fork should be deleted.

[arvindth]

@ybyzek, I've tested this change against some variations of properties files based on your original description in the ticket. However, as the original reporter I would request that you try out this branch on some properties files to ensure that it meets the ask from the ticket.

[ybyzek]

@arvindth awesome work! However, I'm very slammed and won't have time to validate this. Please validate with QA, PM, or others...please don't block on me. Thanks!

[arvindth]

@confluentinc/cli, while reviewing this, note that this depends on an update to the underlying magiconair/properties library, which I've done on a confluentinc fork (confluentinc/properties#1). Please let me know if you think the fork's changes should also go through a PR review.

[DABH]

@arvindth no need for us reviewing that lib, that is between you and @magiconair : )

[DABH]

LGTM