refactor: restore DNSLink redirect to local gateway (#831)

This change restores DNSLink redirect to local gateway as the default setting:

https://docs.ipfs.io → http://127.0.0.1:8080/ipns/docs.ipfs.io/

During the Design Review Call for we've decided to keep the default user experience of loading DNSLink websites from local gateway by default.

Ref. ipfs-inactive/docs#405 (comment)

add-on/src/lib/options.js

@@ -18,7 +18,7 @@ exports.optionDefaults = Object.freeze({
   linkify: false,
   dnslinkPolicy: 'best-effort',
   dnslinkDataPreload: true,
-  dnslinkRedirect: false,
+  dnslinkRedirect: true,
   recoverFailedHttpRequests: true,
   detectIpfsPathHeader: true,
   preloadAtPublicGateway: true,

test/functional/lib/ipfs-request-dnslink.test.js

@@ -34,7 +34,6 @@ describe('modifyRequest processing of DNSLinks', function () {
       ipfsNodeType: 'external',
       peerCount: 1,
       redirect: true,
-      dnslinkRedirect: true, // NOTE: this is opt-in now
       catchUnhandledProtocols: true,
       gwURLString: 'http://127.0.0.1:8080',
       pubGwURLString: 'https://ipfs.io'