Fix indirect libguile dependency in customer import

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@22909 57a11ea4-9604-0410-9ed3-97b8803252fd
Fix indirect libguile dependency in bi_import plugin

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@22910 57a11ea4-9604-0410-9ed3-97b8803252fd