1524 when loading data the data explorer should revert to the data tab

[juliuskarliczek]

Description

Added logic to DataExplorer.py, in which the current tab is changed upon calling loadFromURL() in DataExplorer.py

Fixes # (issue/issues)
Fixes issue #1524

How Has This Been Tested?

local win10 build, loaded data and tab changed

Review Checklist:

[if using the editor, use [x] in place of [ ] to check a box]

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)

Licencing (untick if necessary)

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

[rozyczko]

Looks good!

[rozyczko]

Just a note - there is a separate method for changing tabs in the DE: (line 176)

def changeTabs(self, tab=0):

which could have been used.
But it does not really matter since the functionality is very straightforward.

(Also, to be very nitpicky, the comment is not entirely right, since the switch does not happen after the reading, but during, since we're reading the files in a separate thread... )