[clang-format] Fixes for spaces around C# object initializers

Summary: Fix spaces around typename and [] in C# object initializers.

Reviewers: MyDeveloperDay, klimek, krasimir

Reviewed By: MyDeveloperDay, krasimir

Subscribers: cfe-commits

Tags: #clang-format, #clang

Differential Revision: https://reviews.llvm.org/D72401