doc: Use Octave preference for double quote in docstrings in scripts/ * interp1.m, interp2.m, interp3.m, interpn.m, profexplore.m, profile.m, profshow.m, quadgk.m, lookfor.m, imagesc.m, bzip2.m, gzip.m, parseparams.m, pkg.m, ancestor.m, caxis.m, ezmesh.m, ezmeshc.m, ezsurf.m, ezsurfc.m, hidden.m, hold.m, patch.m, pie.m, pie3.m, quiver.m, quiver3.m, scatter3.m, uicontextmenu.m, uicontrol.m, uipanel.m, uipushtool.m, uitoggletool.m, uitoolbar.m, xlim.m, ylim.m, zlim.m, ismember.m, setxor.m, filter2.m, bicg.m, demo.m, example.m, fail.m, test.m: Use Octave preference for double quote in docstrings in scripts/ directory.

--- a/scripts/testfun/fail.m
+++ b/scripts/testfun/fail.m
@@ -22,7 +22,7 @@
 ## -*- texinfo -*-
 ## @deftypefn  {Function File} {} fail (@var{code})
 ## @deftypefnx {Function File} {} fail (@var{code}, @var{pattern})
-## @deftypefnx {Function File} {} fail (@var{code}, 'warning', @var{pattern})
+## @deftypefnx {Function File} {} fail (@var{code}, "warning", @var{pattern})
 ##
 ## Return true if @var{code} fails with an error message matching
 ## @var{pattern}, otherwise produce an error.  Note that @var{code}