Use temp repl buffer for client local vars tests

[ikappaki]

Hi,

could you please review fix for a test recently introduced with #3275 that appears to have been broken with 4004862.

Traceback (most recent call last):
  cider-connect-sibling-cljs((:cljs-repl-type native-cljs) #<buffer *nrepl-server ~/project:localhost*<2>>)
  cider-nrepl-connect((:cljs-repl-type native-cljs :host "localhost" :port 37791 :project-dir "/root/project/" :server #<process nrepl-server> :server-command "\"emacs\" -Q --batch --eval \"(progn  (setf package-user-dir       \\\"/root/project/.eldev/26.3/packages\\\"       load-path              user-emacs-directory       \\\"/root/project/.eldev/26.3/emacs-dir/\\\"  ) (package-initialize))\" -l test/nrepl-server-mock.el -f nrepl-server-mock-start" :cider-repl-cljs-upgrade-pending nil :session-name nil :repl-type cljs))
  nrepl-start-client-process("localhost" 37791 #<process nrepl-server> #[257 "\301\300!\207" [(:cljs-repl-type native-cljs :host "localhost" :port 37791 :project-dir "/root/project/" :server #<process nrepl-server> :server-command "\"emacs\" -Q --batch --eval \"(progn  (setf package-user-dir       \\\"/root/project/.eldev/26.3/packages\\\"       load-path         (package-initialize))\" -l test/nrepl-server-mock.el -f nrepl-server-mock-start" :cider-repl-cljs-upgrade-pending nil :session-name nil :repl-type cljs))
  y-or-n-p("A dead REPL *cider-repl ~/project:localhost:45251(cljs)* exists.  Reuse? ")
  read-string("A dead REPL *cider-repl ~/project:localhost:45251(cljs)* exists.  Reuse? (y or n) ")
error: (error "Error reading from stdin")```

A temp repl buffer is used so that is closed automatically, and the tests have been reduced to those that use cider-register-cljs-repl-type, since the nbb and shadow are covered by the corresponding integration tests.

Thanks

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Thanks!

If you're just starting out to hack on CIDER you might find this section of its
manual extremely useful.

[bbatsov]

I'm still puzzled how this test was working before, but I appreciate the quick fix!