fix: migrate range.test.js for tap v21

PR #839 was merged after a long time, so the test written for it was
written for a previous version of tap which had the `t.ifError()`
method. The current version has `t.error()` instead.

Introduced-By: a4c13ae

Author: KernelDeimos

test/range.test.js

@@ -58,7 +58,7 @@ test('range starts beyond the end', (t) => {
       headers: { range: '500-' },
     };
     request.get(opts, (err, res, body) => {
-      t.ifError(err);
+      t.error(err);
       t.equal(res.statusCode, 416, 'range error status code');
       t.equal(res.headers['content-range'], 'bytes */11');
       t.equal(body, 'Requested range not satisfiable');