Update example paths and yaml names in README

Two of the the example yaml files no longer exist under the current path.
Updated the yaml file names and path to these files to reflect the current
structure. Per @sbwsg, use v1beta1 as the preferred path.

Author: tedhtchang

examples/README.md

@@ -17,16 +17,16 @@ push to from inside your cluster. If you are following instructions
 
 ```bash
 # To invoke the build-push Task only
-kubectl apply -f examples/taskruns/taskrun.yaml
+kubectl apply -f examples/v1beta1/taskruns/task-output-image.yaml
 
 # To invoke the simple Pipeline
-kubectl apply -f examples/pipelineruns/pipelinerun.yaml
+kubectl apply -f examples/v1beta1/pipelineruns/pipelinerun.yaml
 
 # To invoke the Pipeline that links outputs
-kubectl apply -f examples/pipelineruns/output-pipelinerun.yaml
+kubectl apply -f examples/v1beta1/pipelineruns/output-pipelinerun.yaml
 
 # To invoke the TaskRun with embedded Resource spec and task Spec
-kubectl apply -f examples/taskruns/git-resource-spec-taskrun.yaml
+kubectl apply -f examples/v1beta1/taskruns/git-resource.yaml
 ```
 
 ## Results