[IMP] travis: isolate database_cleanup again

Cherry-pick of d464fb2c59 to 12.0

.travis.yml

@@ -17,8 +17,11 @@ env:
 
   matrix:
   - LINT_CHECK="1"
-  - TESTS="1" ODOO_REPO="OCA/OCB"
-  - TESTS="1" ODOO_REPO="OCA/OCB" MAKEPOT="1"
+  - TESTS="1" ODOO_REPO="OCA/OCB" EXCLUDE="database_cleanup"
+  - TESTS="1" ODOO_REPO="OCA/OCB" INCLUDE="database_cleanup"
+  - TESTS="1" ODOO_REPO="odoo/odoo" EXCLUDE="database_cleanup" MAKEPOT="1"
+  - TESTS="1" ODOO_REPO="odoo/odoo" INCLUDE="database_cleanup" MAKEPOT="1"
+
 
 install:
   - git clone --depth=1 https://github.com/OCA/maintainer-quality-tools.git ${HOME}/maintainer-quality-tools