Update iPad Air 2 simulator to use available sim on Travis

Summary:
Job failing b/c 10.3 doesn't exist, must use 10.3.1

https://travis-ci.org/Instagram/IGListKit/jobs/244977277
Closes Instagram#818

Differential Revision: D5301499

Pulled By: rnystrom

fbshipit-source-id: dc23a67d600027f5afa8d325f8ead805eff5281c

.travis.yml

@@ -39,7 +39,7 @@ env:
    - DESTINATION="OS=10.0,name=iPhone 6s"  SDK="$IOS_SDK" SCHEME="$IOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="YES" RUN_UI_TESTS="NO" POD_LINT="NO"
    - DESTINATION="OS=10.1,name=iPhone 6s"  SDK="$IOS_SDK" SCHEME="$IOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="NO"  RUN_UI_TESTS="NO" POD_LINT="NO"
    - DESTINATION="OS=10.2,name=iPad Air 2" SDK="$IOS_SDK" SCHEME="$IOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="NO"  RUN_UI_TESTS="NO" POD_LINT="NO"
-   - DESTINATION="OS=10.3,name=iPad Air 2" SDK="$IOS_SDK" SCHEME="$IOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="NO"  RUN_UI_TESTS="NO" POD_LINT="NO"
+   - DESTINATION="OS=10.3.1,name=iPad Air 2" SDK="$IOS_SDK" SCHEME="$IOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="NO"  RUN_UI_TESTS="NO" POD_LINT="NO"
 
    - DESTINATION="OS=9.0,name=Apple TV 1080p"  SDK="$TVOS_SDK" SCHEME="$TVOS_SCHEME" RUN_TESTS="NO"  BUILD_EXAMPLE="YES" RUN_UI_TESTS="NO" POD_LINT="NO"
    - DESTINATION="OS=10.0,name=Apple TV 1080p" SDK="$TVOS_SDK" SCHEME="$TVOS_SCHEME" RUN_TESTS="YES" BUILD_EXAMPLE="YES" RUN_UI_TESTS="NO" POD_LINT="NO"