Fix: cider-repl-set-ns no longer changes the repl session type from cljs:shadow to clj

[vemv]

Closes #3236

I could both repro the original issue and verify that this proposed fix works.

The minimal repro was:

(nrepl-sync-request:eval "42"
                         (cider-current-repl nil 'ensure)
                         "my.ns"
                         'tooling)

As soon as one evaluated that code, the cljs repl type would be change to clj.

Thanks much to @jellelicht for his analysis: #3236 (comment)

Cheers - V

[bbatsov]

Looks good to me.