stb should be a dependency but isn't. If the flashlight build doesn't find stb, it downloads it from source, which is bad because there might be multiple headers for the same project if a downstream project uses the stb vcpkg port. This also caused a problem because flashlight tried to install the downloaded stb headers which resulted in some empty directories/could break the port.

Also updates the port commit to have some fixes to the nvcc -std/C++ compiler version.

• Which triplets are supported/not supported? Have you updated the CI baseline?

Same triplets as before. No changes.

• Does your PR follow the maintainer guide?

Yes