fix(major): allowed auto major upgrades when theme has warnings

- currently, we don't allow a no-prompt/auto upgrade of Ghost if the
  theme has warnings
- warnings aren't fatal and we're starting to ship deprecations for v5,
  so CI in Ghost is failing
- this commit ignores warnings during the prompt and updates the
  relevant test

lib/tasks/major-update/ui.js

@@ -104,7 +104,7 @@ module.exports = async function ui(ctx) {
         });
     }
 
-    const autoUpgradeDefault = (!results.error.all.length && !results.warning.all.length);
+    const autoUpgradeDefault = !results.error.all.length;
     const answer = await ctx.ui.confirm(`Are you sure you want to proceed with migrating to Ghost ${ctx.version}?`, autoUpgradeDefault, {prefix: chalk.cyan('?')});
     if (!answer) {
         throw new CliError({

test/unit/tasks/major-update/ui-spec.js

@@ -76,7 +76,7 @@ describe('Unit: Tasks > Major Update > UI', function () {
         await ui(ctx);
         expect(ctx.ui.log.callCount).to.eql(7);
         expect(ctx.ui.confirm.calledTwice).to.be.true;
-        expect(ctx.ui.confirm.args[1][1], 'confirm prompt default should be false').to.be.false;
+        expect(ctx.ui.confirm.args[1][1], 'confirm prompt default should be false').to.be.true;
 
         const output = stripAnsi(ctx.ui.log.args.join(' '));