How to replace a specific line with multiline text in shell

I have line uses: actions/checkout@v3.5.0 (note the indentation at the beginning) which needs to be replaced with multiline text

      uses: actions/checkout@v3.5.0
    - name: Set node version
      run: |-
        echo "NODE_VERSION=$(jq -r '.engines.node // "latest"' package.json)" >> $GITHUB_ENV
    - uses: actions/setup-node@v3
      with:
        node-version: ${{ env.NODE_VERSION }}
    - name: Setup project-level .npmrc file and Run Node18 config fix
      run: |
        curl -u ${{ secrets.CICD_ARTYLAB_PUBLISH_USER }}:${{ secrets.CICD_ARTYLAB_PUBLISH_TOKEN }} --fail "https://someurl/api/npm/auth" >> ${{ env.npm_config_userconfig }}
        if [[ $NODE_VERSION -ge 18 ]]; then
          npm config --location project fix
        fi

I did try placing the multiline text in a file and using that in sed. But didn't work.

sed "s| uses: actions/checkout@v3.5.0|$content|g" edmg-ui-master.yml

Getting below error.

> sed: 1: "s| uses: actions/c ...": unescaped newline inside substitute pattern

Any other ideas to do this?

This might work for you (GNU sed):

sed -E '/uses: actions\/checkout@v3\.5\.0/{x;s/.*/cat contentFile/e
        :a;G;/^(.+)\n(\s*).*/{s///;P;s/[^\n]*(\n|$)//;ba};x;d}' file

This matches the required string, copies the new content into the hold buffer, then inserts the leading white space into each line of the hold buffer.

Prints the result as it processes and deletes the original line.

N.B. The new content is held in a separate file e.g. contentFile and may contain indentation too.