test: add letter-spacing test for zwj emoji (#2650)

package.json

@@ -48,7 +48,7 @@
     "babel-loader": "^8.0.5",
     "babel-plugin-add-module-exports": "^1.0.2",
     "babel-plugin-dev-expression": "^0.2.1",
-    "base64-arraybuffer": "0.2.0",
+    "base64-arraybuffer": "1.0.1",
     "body-parser": "^1.19.0",
     "chai": "4.1.1",
     "chromeless": "^1.5.2",
@@ -118,6 +118,7 @@
   "homepage": "https://html2canvas.hertzen.com",
   "license": "MIT",
   "dependencies": {
-    "css-line-break": "2.0.1"
+    "css-line-break": "2.0.1",
+    "text-segmentation": "^1.0.2"
   }
 }

tests/reftests/text/text.html

@@ -149,5 +149,6 @@
     <span>[AB / CD]</span>
 </div>
 <div>Emojis 🤷🏾‍♂️👨‍👩‍👧‍👦 :)</div>
+<div style="letter-spacing: 2px">Emojis with letter-spacing 🤷🏾‍♂️👨‍👩‍👧‍👦 :)</div>
 </body>
 </html>