Minor release to enable more IDE features.

What's Changed

• Make launchType null for extensions/watchOS by @rockbruno in https://github.com/spotify/sourcekit-bazel-bsp/pull/149
• Add information on test files to the graph report by @rockbruno in https://github.com/spotify/sourcekit-bazel-bsp/pull/150

Full Changelog: https://github.com/spotify/sourcekit-bazel-bsp/compare/0.5.2...0.5.3