fix(测试跟踪): 富文本框显示层级问题

--bug=1017148 --user=陈建星 【测试跟踪】测试计划-查看功能用例的依赖关系图显示评论框 https://www.tapd.cn/55049933/s/1285030

framework/sdk-parent/frontend/src/components/MsMarkDownText.vue

@@ -258,7 +258,6 @@ export default {
 
 .v-note-wrapper {
   display: block !important;
-  position: static !important;
 }
 
 :deep(.dropdown-item.dropdown-images) {

test-track/frontend/src/business/plan/view/comonents/functional/FunctionalTestCaseEdit.vue

@@ -593,10 +593,6 @@ p {
   line-height: 20px;
 }
 
-.head-bar {
-  z-index: 999;
-}
-
 .issues-popover {
   height: 550px;
   overflow: auto;
@@ -627,16 +623,4 @@ p {
 .comment-card :deep(.executeCard) {
   margin-bottom: 5px;
 }
-
-:deep(.el-form-item__content) {
-  z-index: 2;
-}
-
-:deep(.el-scrollbar__bar.is-vertical) {
-  z-index: 3;
-}
-
-.head-bar {
-  z-index: 1;
-}
 </style>