[FIX] upgraded OCA contracts module to the latest stable version.

files/requirements.txt

@@ -47,7 +47,7 @@ odoo12-addon-bi-view-editor==12.0.1.1.0
 odoo12-addon-bi-view-report==12.0.1.0.0.99.dev5
 odoo12-addon-community-maps==12.0.0.2.10
 odoo12-addon-connector==12.0.1.3.0
-odoo12-addon-contract==12.0.8.3.7.99.dev3
+odoo12-addon-contract==12.0.8.7.0
 odoo12-addon-contract-payment-mode==12.0.1.1.0.99.dev5
 odoo12-addon-contract-sale==12.0.3.0.0.99.dev1
 odoo12-addon-contract-sale-invoicing==12.0.1.0.3.99.dev2