Matlab warning in hot_rods post-processing

[rmcdermo]

If I just look at this line in dataplot,

[saved_data,drange] = dataplot(Dataplot_Inputs_File, Working_Dir, Working_Dir, Manuals_Dir, [210]);

then I see this warning in Matlab,

Warning:    usage:  [bnds,rowd,sens,rowp,rowg] = mu(matin,blk,opt) 
> In mu (line 44)
In str2num>protected_conversion (line 96)
In str2num (line 61)
In dvcread (line 41)
In dataplot (line 347)
In FDS_verification_script (line 56) 
dataplot 210...
dataplot completed successfully!
scatplot completed successfully!
verification scripts completed successfully!

I put a few print statements in to try and debug but nothing obvious, so I'm just posting this to remind me to look at it.

@gforney Let's grep on "Warning" in Matlab log also. This has probably been around for awhile.

[rmcdermo]

This Warning issue should be fixed with PR #13884