[clang-format] fix alignment w/o binpacked args

The combination of

- AlignConsecutiveAssignments.Enabled = true
- BinPackArguments = false

would result in the first continuation line of a braced-init-list being
improperly indented (missing a shift) when in a continued function call.
Indentation was also wrong for braced-init-lists continuing a
direct-list-initialization.  Check for opening braced lists in
continuation and ensure that the correct shift occurs.

Fixes https://github.com/llvm/llvm-project/issues/55360

Reviewed By: curdeius

Differential Revision: https://reviews.llvm.org/D125162