fix rst syntax

README.rst

@@ -178,7 +178,7 @@ Requirements for particular toolchains and package sets
 - ``foss*-cuda-mpi`` (proably as `*-mpi, needs testing TODO`)
 
 Finding the Octopus configure wrapper
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 For each Octopus toolchain, there is a Octopus configure wrapper available.
 The wrapper essentially calls the configure script with the right parameters,