Merge pull request #175 from Financial-Times/pa11y_check

Pa11y check update

Makefile

@@ -35,7 +35,7 @@ APP_NAME = $(shell cat package.json 2>/dev/null | $(call JSON_GET_VALUE,name))
 DONE = echo ✓ $@ done
 CONFIG_VARS = curl -fsL https://ft-next-config-vars.herokuapp.com/$1/$(call APP_NAME)$(if $2,.$2,) -H "Authorization: `heroku config:get APIKEY --app ft-next-config-vars`"
 IS_USER_FACING = `find . -type d \( -path ./bower_components -o -path ./node_modules \) -prune -o -name '*.html' -print`
-MAKEFILE_HAS_A11Y = `grep -rli "make a11y" Makefile`
+MAKEFILE_HAS_A11Y = `grep -rli "make a11y\|a11y:" Makefile`
 
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