Convert deploy scripts to use Bazel

Once the first release to Maven Central is completed with Bazel, all maven related files will be removed.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148103405

Dagger 2.9

2.8 release

Dagger 2.7 Release

2.6.1 release

2.6 release

Dagger 2.5 Release

2.4 release

2.3 release

2.2 Release