Automatic merge from submit-queue
error strings should not end with punctuation
**What this PR does / why we need it**:
Delete the end punctuation of error strings
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
https://github.com/golang/go/wiki/CodeReviewComments#error-strings
**Release note**:
```release-note
```
Signed-off-by: yupeng <yu.peng36@zte.com.cn>