Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Gracefully handle SMTP user input errors (e.g. incorrect email addresses) to prevent Sidekiq retries

### What does this MR do?

This MR gracefully handles SMTP input errors (e.g. incorrect or invalid e-mail addresses) to prevent these types of exceptions from causing Sidekiq to retry the task. If these specific exceptions occur, they will be logged, and the e-mail will be dropped from the queue.

### Why was this MR needed?

If you include an author that has a misspelled e-mail address, Sidekiq will keep sending e-mail to all the recipients even if they have already received the e-mail. The only way to recover is to clear the Sidekiq queue.

Note that other exceptions can still be thrown (e.g. `IOError`, `Net::SMTPAuthenticationError`, `Net::SMTPServerBusy`, `Net::SMTPUnknownError`, and `TimeoutError`). If the worker encounters these, Sidekiq should retry the task.

### What are the relevant issue numbers?

Closes https://github.com/gitlabhq/gitlabhq/issues/9560

See merge request !1163

Upgrade browser gem to 1.0.0 to avoid warning in IE11 compatibilty mode

GitLab currently displays the "outdated browser" message if users run Internet Explorer 11 in Compatibility Mode. @fnando [updated the browser gem](https://github.com/fnando/browser/pull/168) to use IE's Trident version to determine the "true" version of IE11.

Closes #2271

See merge request !1188

Ignore empty incoming messages (Reply by email)

We should also update mail_room when https://github.com/tpitale/mail_room/pull/35 goes in, but that can wait a bit.

See merge request !1190

Move changelog entry to 7.14.1

[ci skip]

See merge request !1192

[ci skip]

Move full_host fix changelog entry to 7.14.1

[ci skip]

See merge request !1191

[ci skip]