[CI] Add auto run generate_exports.py to pre-commit

[RattataKing]

It is easy to forget updating C API exports when adding new Python bindings.
This change adds a pre-commit hook that runs generate_exports.py whenever header files under compiler/bindings/c/iree/compiler/ are modified.

[bangtianliu]

Thanks, this is very helpful.

[kuhar]

Looks great, thanks for automating this.

Have you tried adding a new CAPI to see what the output looks like? Could you show an example?

[hanhanW]

Does it print out how to fix the failure (e.g., running the script) when it fails?

[ScottTodd]

This does looks appropriate for a pre-commit hook, thanks.

[RattataKing]

Does it print out how to fix the failure (e.g., running the script) when it fails?

It's included in the pre-commit test, CI will print If you are seeing this message in CI, reproduce locally with: `pre-commit run --all-files`.

[RattataKing]

Have you tried adding a new CAPI to see what the output looks like? Could you show an example?

Declare a test sample in /compiler/bindings/c/iree/compiler/dialects/iree_codegen.h

MLIR_CAPI_EXPORTED bool TestPreCommitForCAPI();

Run pre-commit run --all-files, and get terminal output:

...
Regenerate CAPI export files.............................................Failed
- hook id: generate_capi_exports
- files were modified by this hook