fix: call authorization_error! on IMAP auth failures (#13560) (revert) (#13671)

This reverts commit 7acd239c70 to further
debug upstream issues.

spec/models/concerns/backoffable_shared.rb

@@ -1,43 +0,0 @@
-require 'rails_helper'
-
-shared_examples_for 'backoffable' do
-  let(:obj) { FactoryBot.create(described_class.to_s.underscore.tr('/', '_').to_sym) }
-
-  before do
-    allow(GlobalConfigService).to receive(:load).with('BACKOFF_MAX_INTERVAL_MINUTES', 5).and_return(2)
-    allow(GlobalConfigService).to receive(:load).with('BACKOFF_MAX_INTERVAL_COUNT', 10).and_return(3)
-    # max_interval=2, max_retries=(2-1)+3=4; exhausts on 5th apply_backoff!
-  end
-
-  it 'starts with no backoff' do
-    expect(obj.in_backoff?).to be false
-    expect(obj.backoff_retry_count).to eq 0
-  end
-
-  it 'ramps backoff on each failure' do
-    obj.apply_backoff!
-    expect(obj.backoff_retry_count).to eq 1
-    expect(obj.in_backoff?).to be true
-  end
-
-  it 'caps wait time at max interval' do
-    4.times { obj.apply_backoff! }
-    expect(obj.backoff_retry_count).to eq 4
-    expect(obj.in_backoff?).to be true
-  end
-
-  it 'exhausts backoff and calls prompt_reauthorization! after max retries' do
-    allow(obj).to receive(:prompt_reauthorization!)
-    5.times { obj.apply_backoff! }
-    expect(obj).to have_received(:prompt_reauthorization!)
-    expect(obj.backoff_retry_count).to eq 0
-    expect(obj.in_backoff?).to be false
-  end
-
-  it 'clear_backoff! resets retry count and backoff window' do
-    obj.apply_backoff!
-    obj.clear_backoff!
-    expect(obj.in_backoff?).to be false
-    expect(obj.backoff_retry_count).to eq 0
-  end
-end