fix some spelling mistakes of docs (#1188)

docs/build/auth.md

@@ -257,7 +257,7 @@ credentials are then used to authenticate with the Docker registry.
 
 If both `kubernetes.io/*` and knative flavored basic authentication secret are
 provided, knative will merge the credentials from those two ; knative flavored
-credentials taking precendence over `kubernetes.io/dockerconfigjson` (or
+credentials taking precedence over `kubernetes.io/dockerconfigjson` (or
 `kubernetes.io/dockercfg`) ones.
 
 ### Guiding credential selection

docs/eventing/debugging/README.md

@@ -161,7 +161,7 @@ kubectl --namespace knative-debug get channel chan -o jsonpath='{.status.address
 ```
 
 This should return a URI, likely ending in '.cluster.local'. If it doesn't, then
-it implies that something went wrong during reconcilation. See
+it implies that something went wrong during reconciliation. See
 [Channel Controller](#channel-controller).
 
 We will verify that the two resources that the `chan` creates exist and are

docs/eventing/samples/cronjob-source/README.md

@@ -36,7 +36,7 @@ kubectl apply --filename service.yaml
 ### Create Cron Job Event Source
 
 For each set of cron events you want to request, you need to create an Event
-Source in the same namespace as the destiantion. If you need a different
+Source in the same namespace as the destination. If you need a different
 ServiceAccount to create the Deployment, modify the entry accordingly in the
 yaml.
 
@@ -101,7 +101,7 @@ You can remove the Cron Event Source via:
 kubectl delete --filename cronjob-source.yaml
 ```
 
-Similarily, you can remove the Service via:
+Similarly, you can remove the Service via:
 
 ```shell
 kubectl delete --filename service.yaml