Change develop to master doc

Author: Jocs

src/main/menu/templates/help.js

@@ -34,12 +34,12 @@ export default function () {
     submenu: [{
       label: 'Quick Start',
       click () {
-        shell.openExternal('https://github.com/marktext/marktext/blob/develop/docs/README.md')
+        shell.openExternal('https://github.com/marktext/marktext/blob/master/docs/README.md')
       }
     }, {
       label: 'Markdown syntax',
       click () {
-        shell.openExternal('https://github.com/marktext/marktext/blob/develop/docs/MARKDOWN_SYNTAX.md')
+        shell.openExternal('https://github.com/marktext/marktext/blob/master/docs/MARKDOWN_SYNTAX.md')
       }
     }, {
       label: 'Changelog',