feat(doc): 文档优化

core/README.md

@@ -1,12 +1,12 @@
 ### 调试
-`
+```shell
 kubectl run -i --tty --rm --restart=Never \
   --overrides='{"apiVersion": "v1", "spec": {"nodeSelector": {"kubernetes.io/hostname": "tcc"}}}' \
   --image=busybox:1.28 \
   debug -- sh
-`
+```
 
 ### path core中服务的节点亲和性 使他们只运行在master节点上
-`
+```shell
 kubectl patch -n kube-system deployment coredns --patch-file=patch-affinity.yaml
-`
+```