=head2 C<def_supp_file>
Returns an absolute path to the default suppression file associated to the current session.
-C<undef> will be returned as soon as any of C<< ->tool->suppressions_tag >> or C<< ->tool->suppressions_tag >> are also C<undef>.
+
+C<undef> will be returned as soon as any of C<< ->command->suppressions_tag >> or C<< ->tool->suppressions_tag >> are also C<undef>.
Otherwise, the file part of the name is builded by joining those two together, and the directory part is roughly F<< File::HomeDir->my_home / .perl / Test-Valgrind / suppressions / $VERSION >>.
=cut