xcms: removed unnecessary parts of the code which cause problems with pulsar

[hechth]

FOR CONTRIBUTOR:

• I have read the CONTRIBUTING.md document and this tool is appropriate for the tools-iuc repo.
• License permits unrestricted use (educational + commercial)
• This PR updates an existing tool or tool collection

[bgruening]

@hechth do you know why this is causing problems?

[hechth]

@hechth do you know why this is causing problems?

what do you mean? Why this fix is needed?

[bgruening]

Yes, is there anything we need to fix in pulsar?

[hechth]

@bgruening no - the way the tool works, is that the previous tool somehow write the path to the file into a variable which is kept in the Rdata output and then the next tool loads the file by reading that variable ... but in the end, the raw data which is needed is stored in some global variable that is loaded through some r library anyway, so this whole additional loading layer seems redundant. I'm surprised this even worked before - the problem with pulsar is that the files are apparently written into some staging area where they are no longer available afterwards. So I don't think there is anything to change in pulsar.