Fixes bugs for cloned slicer plots

[DrPaulSharp]

Description

This PR adds code to the cloneTheory routine to ensure frozen datasets are named as such and hence SasView will not confuse them with the original datasets/plots.

Given the now very close functionality with "Freeze Results" and "Freeze Fit Results", the "Send to Data Explorer" button has been renamed "Freeze Datasets".

Fixes #4018

How Has This Been Tested?

Produced slicer plots a fit of the 2D dataset "SILIC010", used the "Freeze Datasets" button on slicer plots, plotted the new dataset and ensured the new plots did not interfere with the proper slicer plot functionality.

Review Checklist:

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Documentation (check at least one)

• There is nothing that needs documenting
• Documentation changes are in this PR
• There is an issue open for the documentation (link?)

Installers

• There is a chance this will affect the installers, if so
  • Windows installer (GH artifact) has been tested (installed and worked)
  • MacOSX installer (GH artifact) has been tested (installed and worked)
  • Wheels installer (GH artifact) has been tested (installed and worked)

Licensing (untick if necessary)

• The introduced changes comply with SasView license (BSD 3-Clause)

[jellybean2004]

Tested branch rebased on top of #4006 and #4014. Tested functionality, looks sound.

Using the button for non-slicer plots, eg. invariant, size distribution, inversion plots, does have some issues, as lines are turned into scatter plots, but that will be a separate issue.