doc: remove non-prime number, PR #21

Co-authored-by: Kento Nozawa <k_nzw@klis.tsukuba.ac.jp>

doc/thmtools-manual.tex

@@ -680,7 +680,7 @@
         For every prime $p$, there is a prime $p'>p$.
         In particular, the list of primes,
         \begin{equation}\label{eq:1}
-          2,3,45,7,\dots
+          2,3,5,7,\dots
         \end{equation}
         is infinite.
       \end{restatable}