Allow Nexus to make nested groups with same name

[searscr]

Description of work

A bug was found in SaveNXSPE where an exception would be raised if trying to create and open a group with the same name as the group you are in. For example creating the group /something/something would raise an exception. This adds a flag for opening data that will allow us to open groups with the same name without corrupting the Nexus address if we try to open the same data multiple times.

Fixes #39672 .
Relates to EWM Defect 12236

To test:

The following script should run and successfully save the file.

import os
import numpy

# Create dummy workspace.
out_ws = CreateSimulationWorkspace(Instrument="MARI", BinParams="0,500,2000")
out_ws.setY(0, numpy.array([10.0, 50.0, 30.0, 60.0]))
AddSampleLog(out_ws, 'Ei', LogText='321', LogType='Number', NumberType='Double')
out_ws.setDistribution(True)

file_path = os.path.join(config["defaultsave.directory"], "NXSPEData.nxspe")

data = RenameWorkspace(out_ws)
SaveNXSPE(data, file_path,Psi=32)

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[AndreiSavici]

Needs release notes. I can still make it fail if I change the last two lines to

RenameWorkspace(out_ws, OutputWorkspace="data/data")
SaveNXSPE("data/data", file_path,Psi=32)

[rboston628]

I am pretty certain, for a workspace named "data", that this line will actually create a a dataset called "/data/data/data". We need a test for this inside SaveNXSETest

[searscr]

Yes you are correct, it is opening /data/data/data. Would a nominal test with the workspace named data be sufficient?

[rboston628]

I believe Andrei still approves. Thank you for adding the more sensible error message and new tests

[cailafinn]

Looks good, just a quick question about the test that's been added:

[cailafinn]

Thanks for updating that test. Looks good to me now.