The process '/Users/runner/hostedtoolcache/opam/2.1.5/arm64/opam' failed with exit code 20

The process 'D:\cygwin\wrapperbin\opam.cmd' failed with exit code 20

An error has been caught in some system package index files, so the system package index files have been re-synchronised, and the system package installation has been retried: the process '/users/runner/hostedtoolcache/opam/2.1.5/arm64/opam' failed with exit code 20

An error has been caught in some system package index files, so the system package index files have been re-synchronised, and the system package installation has been retried: the process 'd:\cygwin\wrapperbin\opam.cmd' failed with exit code 20

Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v2. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v2. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.