delete all duplicate empty blanks

Signed-off-by: Xiang Dai <764524258@qq.com>

Kubernetes-commit: 36065c6dd717c14e0a90131041e20345a7e5e324

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,2 +1,2 @@
-Sorry, we do not accept changes directly against this repository. Please see 
+Sorry, we do not accept changes directly against this repository. Please see
 CONTRIBUTING.md for information on where and how to contribute instead.

CONTRIBUTING.md

@@ -2,6 +2,6 @@
 
 Do not open pull requests directly against this repository, they will be ignored. Instead, please open pull requests against [kubernetes/kubernetes](https://git.k8s.io/kubernetes/).  Please follow the same [contributing guide](https://git.k8s.io/kubernetes/CONTRIBUTING.md) you would follow for any other pull request made to kubernetes/kubernetes.
 
-This repository is published from [kubernetes/kubernetes/staging/src/k8s.io/sample-apiserver](https://git.k8s.io/kubernetes/staging/src/k8s.io/sample-apiserver) by the [kubernetes publishing-bot](https://git.k8s.io/publishing-bot). 
+This repository is published from [kubernetes/kubernetes/staging/src/k8s.io/sample-apiserver](https://git.k8s.io/kubernetes/staging/src/k8s.io/sample-apiserver) by the [kubernetes publishing-bot](https://git.k8s.io/publishing-bot).
 
 Please see [Staging Directory and Publishing](https://git.k8s.io/community/contributors/devel/sig-architecture/staging.md) for more information