Those tests broke because they were declaring an endogenous (var_allows_…) that
is not used in the model, and this is no longer allowed by the preprocessor.
Those variables were introduced by commit
dccabecee7 (on the old ecb-master branch), at the
same time as a second PAC equation was introduced.
The fix consists in making the second PAC equation different from the first
one, defining a different endogenous.
88c38c9ebc