Fix workspace-restricted helm-buffers-list

Now SPC b b and SPC b B can both enjoy the power of helm-buffers-list,
while the former is restricted to the buffers in the current workspace.

modules/completion/helm/autoload/helm.el

@@ -18,6 +18,13 @@
        #'helm-find-files
      #'helm-projectile-find-file)))
 
+;;;###autoload
+(defun +helm/persp-buffer-list ()
+  "A version of `helm-buffers-list', but with its buffer list restricted to the
+current workspace."
+  (interactive)
+  (with-persp-buffer-list nil (helm-buffers-list)))
+
 
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