title: how to change cell value of custom dynamic column in ag-grid
body: <p>i added custom column to ag-grid like this</p>
  
  <pre><code> this.columnDefs.push( {headerName: "Action Status", cellStyle:{"text-align":"center"}});
  </code></pre>
  
  <p>how to change a cell value of this column in runtime ?</p>
  
  <p>i tried this solution but not work</p>
  
  <pre><code>this.gridOptions.api.forEachNodeAfterFilterAndSort(function (rowNode:RowNode) {
     rowNode.columnController.originalColumns[1].colDef.headerCellTemplate="test"
  
  });
  
        this.gridOptions.api.softRefreshView();
          this.gridOptions.api.refreshView();
  </code></pre>