exclude the error folder from sphinx toc (#13354)
exclude the error folder from sphinx toc (#13354)

* exclude the error folder from sphinx toc

* bumping commit for CI

larroy/mxnet,dmlc/mxnet,ForkedReposBak/mxnet,ptrendx/mxnet,leezu/mxnet,reminisce/mxnet,ptrendx/mxnet,dmlc/mxnet,sxjscience/mxnet,szha/mxnet,eric-haibin-lin/mxnet,leezu/mxnet,sxjscience/mxnet,larroy/mxnet,szha/mxnet,ptrendx/mxnet,tlby/mxnet,leezu/mxnet,leezu/mxnet,larroy/mxnet,sxjscience/mxnet,yajiedesign/mxnet,dmlc/mxnet,zhreshold/mxnet,yajiedesign/mxnet,ptrendx/mxnet,zhreshold/mxnet,reminisce/mxnet,tlby/mxnet,zhreshold/mxnet,ptrendx/mxnet,DickJC123/mxnet,DickJC123/mxnet,eric-haibin-lin/mxnet,zhreshold/mxnet,sxjscience/mxnet,dmlc/mxnet,szha/mxnet,ptrendx/mxnet,zhreshold/mxnet,dmlc/mxnet,szha/mxnet,apache/incubator-mxnet,eric-haibin-lin/mxnet,yajiedesign/mxnet,ptrendx/mxnet,ForkedReposBak/mxnet,reminisce/mxnet,ForkedReposBak/mxnet,reminisce/mxnet,szha/mxnet,eric-haibin-lin/mxnet,tlby/mxnet,szha/mxnet,yajiedesign/mxnet,eric-haibin-lin/mxnet,DickJC123/mxnet,tlby/mxnet,ForkedReposBak/mxnet,ForkedReposBak/mxnet,eric-haibin-lin/mxnet,sxjscience/mxnet,yajiedesign/mxnet,larroy/mxnet,ptrendx/mxnet,tlby/mxnet,yajiedesign/mxnet,leezu/mxnet,szha/mxnet,leezu/mxnet,ptrendx/mxnet,zhreshold/mxnet,DickJC123/mxnet,reminisce/mxnet,tlby/mxnet,larroy/mxnet,zhreshold/mxnet,reminisce/mxnet,sxjscience/mxnet,larroy/mxnet,larroy/mxnet,sxjscience/mxnet,ptrendx/mxnet,leezu/mxnet,leezu/mxnet,leezu/mxnet,yajiedesign/mxnet,reminisce/mxnet,yajiedesign/mxnet,apache/incubator-mxnet,apache/incubator-mxnet,ForkedReposBak/mxnet,szha/mxnet,zhreshold/mxnet,reminisce/mxnet,ForkedReposBak/mxnet,apache/incubator-mxnet,eric-haibin-lin/mxnet,sxjscience/mxnet,dmlc/mxnet,tlby/mxnet,eric-haibin-lin/mxnet,ForkedReposBak/mxnet,eric-haibin-lin/mxnet,yajiedesign/mxnet,dmlc/mxnet,tlby/mxnet,larroy/mxnet,larroy/mxnet,szha/mxnet,tlby/mxnet,zhreshold/mxnet,tlby/mxnet,ForkedReposBak/mxnet,dmlc/mxnet,reminisce/mxnet,dmlc/mxnet,sxjscience/mxnet,reminisce/mxnet