JUnit output breaks compatiblity (`deftest`-wrapped) forms executed via `lein test`

```
(ns midje-breakage.core-test
  (:require
   [clojure.test :refer [deftest]]
   [midje.sweet :refer [facts fact =>]]))

(deftest spam
  (fact "It's not ham" "spam" => "spam"))
```
```
$ lein test

lein test midje-breakage.core-test

lein test :only midje-breakage.core-test/spam

ERROR in (spam) (core.clj:2178)
Uncaught exception, not in assertion.
expected: nil
  actual: java.lang.ClassCastException: clojure.lang.Var$Unbound cannot be cast to clojure.lang.Atom
 at clojure.core$reset_BANG_.invoke (core.clj:2178)
    midje.emission.plugins.junit$starting_to_check_fact.invoke (junit.clj:77)
    clojure.lang.Var.invoke (Var.java:415)
    clojure.lang.AFn.applyToHelper (AFn.java:161)
    clojure.lang.Var.applyTo (Var.java:532)
    clojure.core$apply.invoke (core.clj:617)
    midje.emission.api$bounce_to_plugin.doInvoke (api.clj:32)
    clojure.lang.RestFn.invoke (RestFn.java:423)
    midje.emission.api$starting_to_check_fact.invoke (api.clj:77)
    midje.checking.facts$check_one.invoke (facts.clj:30)
    midje.checking.facts$creation_time_check.invoke (facts.clj:35)
    midje_breakage.core_test/fn (core_test.clj:7)
    clojure.test$test_var$fn__7145.invoke (test.clj:701)
    clojure.test$test_var.invoke (test.clj:701)
    user$eval83$test_var_with_selector__92.invoke (NO_SOURCE_FILE:1)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.AFn.applyTo (AFn.java:151)
    clojure.core$apply.invoke (core.clj:619)
    leiningen.core.injected$compose_hooks$fn__17.doInvoke (NO_SOURCE_FILE:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:617)
    leiningen.core.injected$run_hooks.invoke (NO_SOURCE_FILE:1)
    leiningen.core.injected$prepare_for_hooks$fn__22$fn__23.doInvoke (NO_SOURCE_FILE:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.lang.AFunction$1.doInvoke (AFunction.java:29)
    clojure.lang.RestFn.invoke (RestFn.java:408)
    clojure.test$test_all_vars$fn__7149$fn__7156.invoke (test.clj:717)
    clojure.test$default_fixture.invoke (test.clj:671)
    clojure.test$test_all_vars$fn__7149.invoke (test.clj:717)
    clojure.test$default_fixture.invoke (test.clj:671)
    clojure.test$test_all_vars.invoke (test.clj:713)
    clojure.test$test_ns.invoke (test.clj:736)
    clojure.core$map$fn__4207.invoke (core.clj:2487)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.Cons.next (Cons.java:39)
    clojure.lang.RT.boundedLength (RT.java:1654)
    clojure.lang.RestFn.applyTo (RestFn.java:130)
    clojure.core$apply.invoke (core.clj:619)
    clojure.test$run_tests.doInvoke (test.clj:751)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:617)
    user$eval83$fn__149.invoke (NO_SOURCE_FILE:1)
    user$eval83.invoke (NO_SOURCE_FILE:1)
    clojure.lang.Compiler.eval (Compiler.java:6619)
    clojure.lang.Compiler.eval (Compiler.java:6609)
    clojure.lang.Compiler.eval (Compiler.java:6582)
    clojure.core$eval.invoke (core.clj:2852)
    clojure.main$eval_opt.invoke (main.clj:308)
    clojure.main$initialize.invoke (main.clj:327)
    clojure.main$null_opt.invoke (main.clj:362)
    clojure.main$main.doInvoke (main.clj:440)
    clojure.lang.RestFn.invoke (RestFn.java:421)
    clojure.lang.Var.invoke (Var.java:419)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.Var.applyTo (Var.java:532)
    clojure.main.main (main.java:37)

Ran 1 tests containing 1 assertions.
0 failures, 1 errors.
Tests failed.
```

It seems `starting-fact-stream` is not called before `starting-to-check-fact` is.

`lein midje` still works.