[clang-format] Reflow long C# generic type constraints correctly

Summary:
Align sequential generic type constraints on a type.

Indent sequential generic type constraints on different types as continuations.

Do not allow '(' and '<' within a generic type constraint to open new scopes.

Reviewers: krasimir

Subscribers: cfe-commits, MyDeveloperDay

Tags: #clang-format, #clang

Differential Revision: https://reviews.llvm.org/D76597