[RTI-16021] Make spillway OTP 27 compatible

[raz-adroll]

No description provided.

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[abijr]

Instead of duplicating the code, you could add the 2 options to the matrix?

      matrix:
        include:
          - otp: '25.2.1'
            rebar: '3.20.0'
          - otp: '27'
            rebar: '3.24'

[raz-adroll]

Instead of duplicating the code, you could add the 2 options to the matrix?

      matrix:
        include:
          - otp: '25.2.1'
            rebar: '3.20.0'
          - otp: '27'
            rebar: '3.24'

Nice!