vue-treeselect只能选择叶子节点，限制选择等级

<treeselect
                        :disable-branch-nodes="true"  //禁用可打开的节点     
                        v-model="orgInfo"
                        value-format="object"
                        :multiple="false"
                        :load-options="loadOptions"
                        :auto-load-root-options="true"
                        :async="false"
                        @input="closeOnSelOrg"
                        :options="options"
                        alwaysOpen="true"
                >

:disable-branch-nodes=“true”