solo.qli: ~Plotfix: Mv hold(h(2), 'on') between irf_plot() calls

ADD hold(h(i2), 'on') to be between two irf_plot() calls.
==> Plot 2's top and right boundaries+ticks come back (previously disappeared).

@@ -558,6 +558,7 @@ text(h(1), 0, 1.2, str, 'Units', 'normalized')
 yyaxis(h(2), 'left');
 h(2).YScale   = 'log';       % NOTE: Later changed to LIN for non-24h quicklooks.
 h(2).YTick    = [1, 10, 100];
+h(2).YLimMode = 'auto';
==> Correct the y scaling after above change.

Plot used to be OK, but has changed without modifying the solo.qli code,
possibly due to updated irf_spectrogram(). Otherwise unclear why.

modified:   generate_quicklooks_24h_6h_2h.m

mission/solar_orbiter/+solo/+qli/generate_quicklooks_24h_6h_2h.m

@@ -163,10 +163,10 @@ function generate_quicklooks_24h_6h_2h(Data, OutputPaths, Tint24h, logoPath)
 %=======================
 % Fill panel 2: N & |B|
 %=======================
-hold(h(2), 'on');
 if ~isempty(Data.Ne)
   irf_plot(h(2), Data.Ne.tlim(Tint24h), '-', 'color', COLORS(1,:), 'linewidth', LINE_WIDTH);
 end
+hold(h(2), 'on');
 if ~isempty(Data.Npas)
   irf_plot(h(2), Data.Npas.tlim(Tint24h), '-', 'color', COLORS(2,:), 'linewidth', LINE_WIDTH);
 end
@@ -556,8 +556,9 @@ function generate_quicklooks_24h_6h_2h(Data, OutputPaths, Tint24h, logoPath)
 % than where their respective panels are created. Related to
 % irf_plot_axis_align()?
 yyaxis(h(2), 'left');
-h(2).YScale = 'log';       % NOTE: Later changed to LIN for non-24h quicklooks.
-h(2).YTick  = [1, 10, 100];
+h(2).YScale   = 'log';       % NOTE: Later changed to LIN for non-24h quicklooks.
+h(2).YTick    = [1, 10, 100];
+h(2).YLimMode = 'auto';
 
 % Remove overlapping ticks.
 % Automatically set YLim+YTick, or automatically set YLim, or adjust YLim,