fix: Emails not delivered when case does not match

Fixes #2504

spec/fixtures/files/support_without_sender_name.eml

@@ -4,7 +4,7 @@ Content-Type: multipart/alternative; boundary="Apple-Mail=_33A037C7-4BB3-4772-AE
 Subject: Discussion: Let's debate these attachments
 Date: Tue, 20 Apr 2020 04:20:20 -0400
 In-Reply-To: <4e6e35f5a38b4_479f13bb90078178@small-app-01.mail>
-To: "Replies" <care@example.com>
+To: "Replies" <Care@example.com>
 References: <4e6e35f5a38b4_479f13bb90078178@small-app-01.mail>
 Message-Id: <0CB459E0-0336-41DA-BC88-E6E28C697DDB@chatwoot.com>
 X-Mailer: Apple Mail (2.1244.3)

spec/mailboxes/support_mailbox_spec.rb

@@ -66,6 +66,16 @@ RSpec.describe SupportMailbox, type: :mailbox do
       end
     end
 
+    describe 'Sender with upcase mail address' do
+      let(:support_mail_without_sender_name) { create_inbound_email_from_fixture('support_without_sender_name.eml') }
+      let(:described_subject) { described_class.receive support_mail_without_sender_name }
+
+      it 'create a new inbox with the email case insensitive' do
+        described_subject
+        expect(conversation.inbox.id).to eq(channel_email.inbox.id)
+      end
+    end
+
     describe 'handle inbox contacts' do
       let(:contact) { create(:contact, account: account, email: support_mail.mail.from.first) }
       let(:contact_inbox) { create(:contact_inbox, inbox: channel_email.inbox, contact: contact) }