Fix Docker Android tests container issue related to the JSC (facebook#24360)

Summary:
[Fixes an issue where the Docker Android tests container cannot be built.](facebook#24276 (comment)) The JSC is now pulled from the npm registry, so we need to run `yarn` prior to pulling the Gradle dependencies.

[Android] [Fixed] - Fixed React Native Android tests Docker container issue related to the JSC
Pull Request resolved: facebook#24360

Differential Revision: D14842534

Pulled By: hramos

fbshipit-source-id: 3a1a714879e9c52a812b1077dce449470c30bddd

Author: hramos

.circleci/Dockerfiles/Dockerfile.android

@@ -8,10 +8,10 @@
 #
 # The base image is expected to remain relatively stable, and only
 # needs to be updated when major dependencies such as the Android
-# SDK or NDK are updated. 
+# SDK or NDK are updated.
 #
-# In this Android Test image, we download the latest dependencies 
-# and build a Android application that can be used to run the 
+# In this Android Test image, we download the latest dependencies
+# and build a Android application that can be used to run the
 # tests specified in the scripts/ directory.
 #
 FROM reactnativecommunity/react-native-android
@@ -42,16 +42,11 @@ RUN buck fetch ReactAndroid/src/androidTest/...
 RUN buck build ReactAndroid/src/main/java/com/facebook/react
 RUN buck build ReactAndroid/src/main/java/com/facebook/react/shell
 
-ADD gradle /app/gradle
-ADD gradlew /app/gradlew
-ADD settings.gradle /app/settings.gradle
-ADD build.gradle /app/build.gradle
-ADD react.gradle /app/react.gradle
+ADD . /app
 
-RUN ./gradlew :ReactAndroid:downloadBoost :ReactAndroid:downloadDoubleConversion :ReactAndroid:downloadFolly :ReactAndroid:downloadGlog :ReactAndroid:downloadJSC
+RUN yarn
 
-RUN ./gradlew :ReactAndroid:packageReactNdkLibsForBuck -Pjobs=1
+RUN ./gradlew :ReactAndroid:downloadBoost :ReactAndroid:downloadDoubleConversion :ReactAndroid:downloadFolly :ReactAndroid:downloadGlog
 
-ADD . /app
+RUN ./gradlew :ReactAndroid:packageReactNdkLibsForBuck -Pjobs=1
 
-RUN yarn