[llvm] [Dexter] Remove clang-opt-bisect analyzer tool (PR #128165)

[Stephen Tozer via llvm-commits]

https://github.com/SLTozer approved this pull request.

Thought we'd removed this already! There are no other lingering references to the tool or tests that depend on it AFAICT, so fully removing this file should be fine.

https://github.com/llvm/llvm-project/pull/128165