Downgrade to electron 20.3.4 to fix crash on call hangup (#459)

Co-authored-by: t3chguy <[email protected]>
Co-authored-by: ElementRobot <[email protected]>
Fixes element-hq/element-web#23783
Fixes undefined

Author: 3 people

package.json

@@ -70,7 +70,7 @@
     "babel-jest": "^28.1.3",
     "chokidar": "^3.5.2",
     "detect-libc": "^1.0.3",
-    "electron": "^20",
+    "electron": "20.3.4",
     "electron-builder": "^23.6.0",
     "electron-builder-squirrel-windows": "^23.6.0",
     "electron-devtools-installer": "^3.1.1",