Increase nrepl mock server conn timeout period for recently introduced sibling tests

[ikappaki]

Hi,

can you please review follow up PR to #3275 to address a spurious failure currently seen on master with one of the newly introduced sibling regression tests:

========================================
cider-connect-sibling-cljs sets nrepl client local vars correctly for a custom cljs REPL type project

Traceback (most recent call last):
  cider-connect-sibling-cljs((:cljs-repl-type native-cljs) #<buffer *nrepl-server ~/project:localhost*>)
  cider--gather-connect-params(nil #<buffer *nrepl-server ~/project:localhost*>)
  error("This is not a REPL or SERVER buffer; is there an active REPL?")
error: (error "This is not a REPL or SERVER buffer; is there an active REPL?")

There was a call to wait for the mock server process to wait for 2 seconds for the process to start up, but this seems to be borderline low for ms-windows runners, so it is now increased to 5 secs.

I've also replaced the polling function in the nrepl tests with a copy from the one from integration tests, which also throws an error if the condition is not met (rather than silently continuing).

Thanks

---

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Thanks!

[bbatsov]

Looks good! Thanks!

[bbatsov]

@ikappaki I see some weird errors in the tests right now:

E.g. https://app.circleci.com/pipelines/github/clojure-emacs/cider/1432/workflows/d556f686-3736-4b23-8150-07578bef141a/jobs/6934

cider-connect-sibling-cljs sets nrepl client local vars correctly for a custom cljs REPL type project

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")```

Is this some flakiness again? 

[ikappaki]

(should be addressed with #3297)