Fix RSpec/ContextWording cop (#24739)

spec/models/custom_emoji_spec.rb

@@ -8,7 +8,7 @@ RSpec.describe CustomEmoji, type: :model do
 
     let(:custom_emoji) { Fabricate(:custom_emoji, shortcode: shortcode) }
 
-    context 'shortcode is exact' do
+    context 'when shortcode is exact' do
       let(:shortcode) { 'blobpats' }
       let(:search_term) { 'blobpats' }
 
@@ -17,7 +17,7 @@ RSpec.describe CustomEmoji, type: :model do
       end
     end
 
-    context 'shortcode is partial' do
+    context 'when shortcode is partial' do
       let(:shortcode) { 'blobpats' }
       let(:search_term) { 'blob' }
 
@@ -32,7 +32,7 @@ RSpec.describe CustomEmoji, type: :model do
 
     let(:custom_emoji) { Fabricate(:custom_emoji, domain: domain) }
 
-    context 'domain is nil' do
+    context 'when domain is nil' do
       let(:domain) { nil }
 
       it 'returns true' do
@@ -40,7 +40,7 @@ RSpec.describe CustomEmoji, type: :model do
       end
     end
 
-    context 'domain is present' do
+    context 'when domain is present' do
       let(:domain) { 'example.com' }
 
       it 'returns false' do