Gate wtfnode behind WTF_NODE env var

After thinking about it some more it's probably mostly only useful to
see the output when the tests are hanging. Otherwise there's a lot of
noise about Jest child processes and pipes.

package.json

@@ -143,9 +143,6 @@
         "lines": 40
       }
     },
-    "modulePathIgnorePatterns": [
-      "<rootDir>/release"
-    ],
     "testTimeout": 30000,
     "globalSetup": "<rootDir>/test/globalSetup.ts",
     "modulePathIgnorePatterns": [