Merge pull request kubernetes#1421 from yuzhiquan/patch-typo

cleanup(enhancements): typo

Author: k8s-ci-robot

keps/sig-node/0009-node-heartbeat.md

@@ -283,7 +283,7 @@ both real clusters and Kubemark.
 GA:
 - Enabled by default for a release with no complaints.
 - Frequency of NodeStatus defaulted to 5m
-- kubectl describe node showing information from corrsponding Lease object
+- kubectl describe node showing information from corresponding Lease object
 
 
 ## Implementation History

keps/sig-node/20190129-pid-limiting.md

@@ -189,4 +189,4 @@ GA
 ### Version 1.15
 
 - Graduate `SupportNodePidsLimit` to beta by adding node e2e test
-  coverage for node cgrop isoation.
+  coverage for node cgroup isoation.

keps/sig-node/20190131-runas-groupid.md

@@ -228,7 +228,7 @@ Note that this change does not introduce an equivalent field called runAsNonRoot
 and PodSecurityContext. There was ongoing discussion about this field at PR [#62216](https://github.com/kubernetes/kubernetes/pull/62217)
 The summary of this discussion seems as follows:-
 - Use PSP MustRunAs Group strategy to guarantee that Pod never runs with 0 as Primary Group ID.
-- Using the PSP MustRunaAs Group strategy forces Pod to always specify a RunAsGroup
+- Using the PSP MustRunAs Group strategy forces Pod to always specify a RunAsGroup
 - RunAsGroup field when specified in PodSpec, will always override USER field in Dockerfile
 
 There are other potentially unresolved discussions in that PR which need a followup.