build(deps): bump llvm-project from 7bc5ade to 783f862

Bumps [llvm-project](https://github.com/Xilinx/llvm-aie) from `7bc5ade` to `783f862`.
- [Release notes](https://github.com/Xilinx/llvm-aie/releases)
- [Commits](Xilinx/llvm-aie@7bc5ade...783f862)

---
updated-dependencies:
- dependency-name: llvm-project
  dependency-version: 783f8625d541281eea582e481de9ef08f45c7b35
  dependency-type: direct:production
...

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Author: dependabot[bot]