fixup: add indentation after template head

Co-authored-by: Jan Schultke <[email protected]>

Author: dietmarkuehl

source/exec.tex

@@ -6104,7 +6104,7 @@
 
 \begin{itemdecl}
 template<@\libconcept{receiver}@ R>
-@\exposid{state}@<R> connect(R&& recv);
+  @\exposid{state}@<R> connect(R&& recv);
 \end{itemdecl}
 
 \begin{itemdescr}