Temporarily disable Android instrumentation tests

Summary:
Android instrumentation tests keep failing due to `java.lang.RuntimeException: java.lang.RuntimeException: Timed out waiting for JS thread`.

An [earlier job](https://circleci.com/gh/facebook/react-native/17064) based off commit [c31a65](facebook/react-native@c31a656) finished successfully, yet [this job](https://circleci.com/gh/facebook/react-native/17070), triggered by the very [next commit](facebook/react-native@e82c2fb), failed Android instrumentation tests even though that commit touches no Android code.

You can see from the [Circle history](https://circleci.com/gh/facebook/react-native/tree/master) that this test has been consistently failing for the same time out reason.

I am disabling Android instrumentation tests as they are not providing any useful signal a this point in time.

Debug and fix instrumentation tests, and re-enable them.
Closes facebook/react-native#13239

Differential Revision: D4810775

Pulled By: hramos

fbshipit-source-id: 8866f9208ec3b5ac5f0ed2f6c2cf58c5b5825830

circle.yml

@@ -73,7 +73,7 @@ test:
     # build test APK
     - buck install ReactAndroid/src/androidTest/buck-runner:instrumentation-tests --config build.threads=1
     # run installed apk with tests
-    - node ./scripts/run-android-ci-instrumentation-tests.js --retries 3 --path ./ReactAndroid/src/androidTest/java/com/facebook/react/tests --package com.facebook.react.tests
+    # - node ./scripts/run-android-ci-instrumentation-tests.js --retries 3 --path ./ReactAndroid/src/androidTest/java/com/facebook/react/tests --package com.facebook.react.tests
 
     # Android e2e test
     - source scripts/circle-ci-android-setup.sh && retry3 node ./scripts/run-ci-e2e-tests.js --android --js --retries 2