Apply more suggestions from magit

Also apply these suggestions:

Once you have done that, you have to explicitly upgrade ‘seq’:

  M-x package-upgrade seq \‘RET’

Then you also must make sure the updated version is loaded,
by evaluating this form:

  (progn (unload-feature ’seq t) (require ’seq))

Change-Id: I51dcbfdea7b575c17adff616bcd1a17487bd732a

Author: twmr

run-tests.sh

@@ -8,6 +8,8 @@ EMACS="${EMACS:=emacs}"
 INIT_PACKAGE_EL="(progn
   (require 'package)
   (setq package-install-upgrade-built-in t)
+  (package-install 'seq)
+  (progn (unload-feature 'seq t) (require 'seq))
   (push '(\"melpa\" . \"https://melpa.org/packages/\") package-archives)
   (package-initialize))"