Bump codemirror version to 5.49.8

Signed-off-by: Yukai Huang <yukaihuangtw@gmail.com>

Author: Yukaii

package-lock.json

@@ -103,7 +103,7 @@
     "ws": "~7.1.1"
   },
   "devDependencies": {
-    "@hackmd/codemirror": "~5.49.5",
+    "@hackmd/codemirror": "~5.49.8",
     "@hackmd/emojify.js": "^2.1.0",
     "@hackmd/idle-js": "~1.0.1",
     "@hackmd/js-sequence-diagrams": "~0.0.1-alpha.3",