FEATURE: add setting auto_approve_email_domains to auto approve users (#9323)

* FEATURE: add setting `auto_approve_email_domains` to auto approve users

This commit adds a new site setting `auto_approve_email_domains` to
auto approve users based on their email address domain.

Note that if a domain already exists in `email_domains_whitelist` then
`auto_approve_email_domains` needs to be duplicated there as well,
since users won’t be able to register with email address that is
not allowed in `email_domains_whitelist`.

* Update config/locales/server.en.yml

Co-Authored-By: Robin Ward <robin.ward@gmail.com>

spec/models/invite_redeemer_spec.rb

@@ -59,7 +59,7 @@ describe InviteRedeemer do
   end
 
   describe "#redeem" do
-    fab!(:invite) { Fabricate(:invite) }
+    fab!(:invite) { Fabricate(:invite, email: "foobar@example.com") }
     let(:name) { 'john snow' }
     let(:username) { 'kingofthenorth' }
     let(:password) { 'know5nOthiNG' }
@@ -102,6 +102,16 @@ describe InviteRedeemer do
       expect(user.approved).to eq(true)
     end
 
+    it "should redeem the invite if invited by non staff and approve if email in auto_approve_email_domains setting" do
+      SiteSetting.must_approve_users = true
+      SiteSetting.auto_approve_email_domains = "example.com"
+      user = invite_redeemer.redeem
+
+      expect(user.name).to eq(name)
+      expect(user.username).to eq(username)
+      expect(user.approved).to eq(true)
+    end
+
     it "should not blow up if invited_by user has been removed" do
       invite.invited_by.destroy!
       invite.reload