pnpm.configHook: improve error message when install fails due to hash (#397491)

    runHook prePnpmInstall

    pnpm install \

    if ! pnpm install \

        --offline \

        --ignore-scripts \

        "${pnpmInstallFlags[@]}" \

        --frozen-lockfile

    then

        echo

        echo "ERROR: pnpm failed to install dependencies"

        echo

        echo "If you see ERR_PNPM_NO_OFFLINE_TARBALL above this, follow these to fix the issue:"

        echo '1. Set pnpmDeps.hash to "" (empty string)'

        echo "2. Build the derivation and wait for it to fail with a hash mismatch"

        echo "3. Copy the 'got: sha256-' value back into the pnpmDeps.hash field"

        echo

        exit 1

    fi

    echo "Patching scripts"