Replaces then(null, done) with .catch(done), OCD on blank lines

No issue

core/test/integration/model/model_permissions_spec.js

@@ -37,7 +37,7 @@ describe('Permission Model', function () {
             foundPermissions.models.length.should.be.above(0);
 
             done();
-        }).then(null, done);
+        }).catch(done);
     });
 
     it('can findOne', function (done) {

core/test/integration/model/model_settings_spec.js

@@ -212,5 +212,4 @@ describe('Settings Model', function () {
             }).catch(done);
         });
     });
-
 });

core/test/integration/model/model_tags_spec.js

@@ -346,10 +346,7 @@ describe('Tag Model', function () {
                     postWithTag.related('tags').length.should.equal(1);
                     done();
                 }).catch(done);
-
             });
         });
-
     });
-
 });

core/test/integration/model/model_users_spec.js

@@ -22,7 +22,7 @@ describe('User Model', function run() {
     afterEach(function (done) {
         testUtils.clearData().then(function () {
             done();
-        }, done);
+        }).catch(done);
     });
 
     describe('Registration', function runRegistration() {
@@ -392,5 +392,4 @@ describe('User Model', function run() {
             });
         });
     });
-
 });