Format .bzl files with buildifier

This is a part of a large-scale change: [] . All .bzl files are being formatted with buildifier.

To format a file manually run `buildifier path/to/file.bzl`. Integration with `g4 fix` will be available later, but you can try using `g4 fix --format=bzl`.

Tested:
    tap_presubmit
    Some tests failed; test failures are believed to be unrelated to this CL

BEGIN_PUBLIC
Format .bzl files with buildifier
END_PUBLIC

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=203461813

java/google/registry/xjc/generated_files.bzl

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 #
 #      .'``'.      ...
 #     :o  o `....'`  ;