1783: Reset transforms for new plots

[krzywon]

Description

This resets the data transforms held by the Data objects on the creation of new plots.

Fixes #1783
Refs #3021

How Has This Been Tested?

Running from source, I tested plotting, changing scale, zoom, etc. I then replotted the same data in multiple ways (fit, new plot) and the new plots display in their default state.

Review Checklist:

Documentation (check at least one)

• There is nothing that needs documenting
• Documentation changes are in this PR (inline)
• 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)

Licencing (untick if necessary)

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

[butlerpd]

The fix seems reasonable as an interim, waiting for the transform to be owned by the plot and eventually for the full plot refactoring.

Testing shows that all the concerns raised in #1783 have indeed been addressed by this change. I do note a very strange auto range setting in that the home button autoranges only on the fit line from the linear fit (so usually a much smaller window than the full window) but that is clearly independent of anything done by this PR.