remove instance with h where it should be Ts

[albheim]

Looking through some old issues I saw #447 which seemed mostly resolved, though there was this one random occurrence of h which was not even referenced in the function body, so it felt like it should be removed since it could accidentally lead to bugs with silently accepting the h and returning something other than intended.

[codecov[bot]]

Codecov Report

Merging #832 (b2dff5d) into master (1e1512e) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #832   +/-   ##
=======================================
  Coverage   97.14%   97.14%           
=======================================
  Files           4        4           
  Lines         315      315           
=======================================
  Hits          306      306           
  Misses          9        9           

[JuliaControlBot]

This is an automated message. Plots were compared to references. 11/11 images have changed, see differences below. After pulling this PR, please update the reference images by creating a PR to ControlExamplePlots.jl here. Difference	Reference Image	New Image
:x: 0.047
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:heavy_check_mark: 0.001
:heavy_check_mark: 0.001
:heavy_check_mark: 0.007
:heavy_check_mark: 0.003
:heavy_check_mark: 0.0
:warning: 0.028
:x: 0.06
:heavy_check_mark: 0.0
:warning: 0.017