discard the buffer (link.csv)

[cleemansen]

Hello @annescharf,

this PR discards the buffer-file (link.csv). The file is only accessible during the transformation by the app only. With this change the file is not a MoveApps artifacts anymore. So it is not downloadable by the user anymore.

I discussed this with @andreakoelzsch . Background is:

• the file link.csv can become very large. MoveApps has to persist the file.
• the file content contains a lot of redundant information; for most MoveApps user the file content is useless

[annescharf]

absolutely agree. If someone wants a csv of the data they can use the app rds2csv