Make sure the y-axis range changes when limits update.

docs/source/release/v6.1.0/mantidworkbench.rst

@@ -37,5 +37,6 @@ Bugfixes
 - First time dialog box will not appear recurrently, if user selected their choice of facility
   and instrument at least once and checked "Do not show again until next version".
 - Fixed a bug that would cause a crash if the user right clicked on the plot in the instrument view pick tab after the stored curves were cleared.
+- The y-axis in the instrument view's pick tab will now rescale if the range changes.
 
 :ref:`Release 6.1.0 <v6.1.0>`

qt/widgets/instrumentview/src/MiniPlotMpl.cpp

@@ -124,6 +124,7 @@ void MiniPlotMpl::setData(std::vector<double> x, std::vector<double> y,
   // is very different we need ensure the scale is tight enough to
   // see newer plots so we force a recalculation from the data
   axes.relim();
+  axes.autoscaleView();
   replot();
 }