Fix typo.

dune/solvers/iterationsteps/blockgssteps.hh

@@ -208,7 +208,7 @@ auto truncateSymmetrically(LinearSolver&& linearSolver) {
 
 namespace LocalSolverRegularizer {
 
-// a suitable value for defaultDiagRagularization could be 1e-10
+// a suitable value for defaultDiagRegularization could be 1e-10
 // nevertheless, the default is 0 to avoid unintentional regularization
 static constexpr double defaultDiagRegularizeParameter = 0;