Install bazel on Travis via the official Bazel releases instead of via the custom apt repository, which is cleared after a new beta is released.
Install bazel on Travis via the official Bazel releases instead of via the custom apt repository, which is cleared after a new beta is released.

Verified in: https://github.com/google/dagger/pull/772
Conversation in: https://github.com/bazelbuild/bazel/issues/1821

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=158998542

google/dagger,ze-pequeno/dagger,ze-pequeno/dagger,ze-pequeno/dagger,ze-pequeno/dagger,cgruber/dagger,ronshapiro/dagger,hansonchar/dagger,ronshapiro/dagger,dushmis/dagger,hansonchar/dagger,ronshapiro/dagger,google/dagger,google/dagger,cgruber/dagger,cgruber/dagger,dushmis/dagger,hansonchar/dagger,google/dagger