fix by some review advice

Signed-off-by: TonsnakeLin <lpbgytong@163.com>

docs/design/2022-01-04-integer-shard-index.md

@@ -57,7 +57,7 @@ The followers is the scalability of hot index and shard index.
 
 Computing formula of scalability is  as bellow: `qps1` is the qps before expansion, `tikv1` is the tikv node count before expansion; `qps2` is the qps after expansion, `tikv2` is the tikv node count afterexpansion.
 
-![image-20220301152240006](.\imgs\scalability-formula.png)
+<img alt="CNF 200" src=".\imgs\scalability-formula.png" width="200pt"/>
 
 
 
@@ -401,12 +401,6 @@ We can use expression index directly other than as the prefix of a index. e.g. r
 
 
 
-## Questions
-
-As I know @tiancaiamao is intended to do the shard index more comprehensively.
-
-
-
 ## Unresolved questions
 
 ### Shard Index Only Support Unique Secondary Index