Fix triggering event range widget

[ericpre]

Fix #2950 and some errors when plotting or updating a Signal1D plot with an empty slice of data.

Progress of the PR

• Trigger event when widget is changed (910e854)
• avoid error with calculating limits in autoscaling code of Signal1D which occurs when plotting an empty slice of data
• improve coverage
• add an changelog entry in the upcoming_changes folder (see upcoming_changes/README.rst),
• Check formatting changelog entry in the readthedocs doc build of this PR (link in github checks)
• add tests,
• ready for review.

[codecov]

Codecov Report

Merging #2952 (455ec3d) into RELEASE_next_patch (90b0349) will increase coverage by 0.02%.
The diff coverage is 89.47%.

@@                  Coverage Diff                   @@
##           RELEASE_next_patch    #2952      +/-   ##
======================================================
+ Coverage               80.76%   80.78%   +0.02%     
======================================================
  Files                     209      209              
  Lines                   32688    32691       +3     
  Branches                 7318     7320       +2     
======================================================
+ Hits                    26401    26411      +10     
+ Misses                   4522     4516       -6     
+ Partials                 1765     1764       -1     

Impacted Files	Coverage Δ
hyperspy/roi.py	85.17% <ø> (+0.44%)	⬆️
hyperspy/drawing/signal1d.py	80.05% <88.23%> (+1.31%)	⬆️
hyperspy/drawing/_widgets/range.py	89.65% <100.00%> (+0.08%)	⬆️
hyperspy/interactive.py	86.79% <100.00%> (ø)

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