Layout layer: counsel-projectile: requires fix

Guard :requires against ivy not projectile. projectile is already owned by
buil-in spacemacs-project layer, so it's always t.

This prevents install of ivy, counsel, swiper and counsel-projectile
packages regardless of helm layer

CHANGELOG.develop

@@ -1040,6 +1040,7 @@ Other:
   - Used return value from advised function in =spacemacs//yank-indent-region=
     (thanks to Brandon T. Willard)
   - Fixed canceling =spacemacs/ace-buffer-links= (thanks to duianto)
+  - Required =ivy= to load =counsel-projectile= (thanks to Thanh Vuong)
 *** Layer changes and fixes
 **** Agda
 - Fixes

layers/+spacemacs/spacemacs-layouts/packages.el

@@ -15,7 +15,7 @@
         ivy
         persp-mode
         spaceline
-        (counsel-projectile :requires projectile)))
+        (counsel-projectile :requires ivy)))