Hide "Edited" when note is transformed or resolved

Makes `Note#edited?` return `false` when the note body was not edited

app/models/note.rb

@@ -313,6 +313,14 @@ class Note < ActiveRecord::Base
     !system?
   end
+  # Since we're using `updated_at` as `last_edited_at`, it could be touched by transforming / resolving a note.
+  # This makes sure it is only marked as edited when the note body is updated.
+  def edited?
+    return false if updated_by.blank?
+
+    super
+  end
+
   def cross_reference_not_visible_for?(user)
     cross_reference? && !all_referenced_mentionables_allowed?(user)
   end

changelogs/unreleased/57330-fix-comment-edited.yml

+---
+title: Fix notes being marked as edited after resolving
+merge_request: 26143
+author:
+type: fixed

spec/models/note_spec.rb

@@ -208,6 +208,24 @@ describe Note do
     end
   end
+  describe "edited?" do
+    let(:note) { build(:note, updated_by_id: nil, created_at: Time.now, updated_at: Time.now + 5.hours) }
+
+    context "with updated_by" do
+      it "returns true" do
+        note.updated_by = build(:user)
+
+        expect(note.edited?).to be_truthy
+      end
+    end
+
+    context "without updated_by" do
+      it "returns false" do
+        expect(note.edited?).to be_falsy
+      end
+    end
+  end
+
   describe "confidential?" do
     it "delegates to noteable" do
       issue_note = build(:note, :on_issue)