Fixed regex incident.

src/process/markov/definition.tex

@@ -31,7 +31,7 @@
     \begin{enumerate}
         \item For each $t \ge 0$, $\bp_t \one = \one$.
         \item For each $t \ge 0$, $\bp_t$ is a positive linear functional.
-    \end\{enumerate\}
+    \end{enumerate}
 
     known as the \textbf{semigroup} of $\bracs{P_t|t \ge 0}$.
 \end{definition}