Remove unnecessary code block and clean up the transition from Gierer-Meinhardt to Gray-Scott in the Turing instability documentation.

Author: Daniel Precioso, PhD

modules/pde-1d/turing-instability.qmd

@@ -431,8 +431,6 @@ def gray_scott_jacobian(u_star, v_star, f=0.040, k=0.060):
 ```
 
 That is the whole bridge from Gierer-Meinhardt to Gray-Scott. Keep the eigenvalue scan, replace the Jacobian, replace the boundary spectrum, then sort the unstable modes and read off the dominant one.
-```
-:::
 
 ## Compare Two Cases