Support new TOML format for rust-toolchain

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• Is this related to the actions-rs Actions? If you think it’s a problem related to Github Actions in general, use GitHub Community forum instead: https://github.community
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• Is this something you can debug and fix? Send a pull request! Bug fixes and documentation fixes are welcome.

Motivation

As announced with Rustup 1.23.0 and documented here, there is a new TOML syntax for the rust-toolchain file which should be supported by this action.

Workflow Failure

Additionally using the TOML syntax without specifying the toolchain input will cause the workflow to fail.

[shonfeder]

Your hint helped me, thanks @Kixunil. To make the hint more explicit:

If you’re using a toml rust-toolchain file, you can just replace

      - name: Setup rust toolchain
        uses: actions-rs/toolchain@v1

with

      - name: Setup rust toolchain
        run: rustup show

[Kixunil]

Hint for people who got bitten by this: just run rustup show, you probably don’t need this whole project then.

Yes, it’s retarded workaround/name for a command but better than waiting eternity for someone to fix this.