Auto merge of #27520 - brson:bump, r=alexcrichton

This probably wants to go in tomorrow. If it lands today then there will be one day where nightly is on 1.4 and stable is still on 1.1. Not a big deal either way.

mk/main.mk

@@ -13,7 +13,7 @@
 ######################################################################
 
 # The version number
-CFG_RELEASE_NUM=1.3.0
+CFG_RELEASE_NUM=1.4.0
 
 # An optional number to put after the label, e.g. '.2' -> '-beta.2'
 # NB Make sure it starts with a dot to conform to semver pre-release