:+1: version and update docs

CHANGES.md

@@ -1,6 +1,10 @@
 # CHANGES
 
-## v4.2.20-RC
+## v4.2.21-RC
+
+* 
+
+## v4.2.20
 
 * Improvement: Error message when the password is too short
 * Improvement: Repeat XSS processing as a countermeasure against nesting 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "growi",
-  "version": "4.2.20-RC",
+  "version": "4.2.21-RC",
   "description": "Team collaboration software using markdown",
   "tags": [
     "wiki",