Update thermostats.py - fix latex error (#91)

Co-authored-by: Michele Ceriotti <[email protected]>

examples/thermostats/thermostats.py

@@ -586,6 +586,7 @@
 #
 #    (\dot{p},\dot{\mathbf{s}}) = -\mathbf{A}_p (p,\mathbf{s}) +
 #    \mathbf{B}_p (\xi,\boldsymbol{\xi})
+
 #
 # Here :math:`\mathbf{A}_p` is the *drift matrix* and  :math:`\mathbf{B}_p`
 # is a diffusion matrix which, for canonical sampling, is determined by the target