[JENKINS-67098] Render summary graph with GET or POST

Allow GET requests for the graph.  The page performing the request is
defined in groovy and I don't know how to configure the groovy page to
make the request with POST rather than GET.

src/main/java/hudson/plugins/testng/TestNGProjectAction.java

@@ -20,7 +20,6 @@
 import org.kohsuke.stapler.Stapler;
 import org.kohsuke.stapler.StaplerRequest;
 import org.kohsuke.stapler.StaplerResponse;
-import org.kohsuke.stapler.verb.POST;
 
 /**
  * Action to associate the TestNG reports with the project
@@ -107,7 +106,7 @@ public String getSearchUrl() {
     * @param rsp -
     * @throws IOException -
     */
-   @POST
+   // @org.kohsuke.stapler.verb.POST // POST blocks graph rendering in groovy web page
    public void doGraph(final StaplerRequest req,
                       StaplerResponse rsp) throws IOException {
       if (newGraphNotNeeded(req, rsp)) {
@@ -144,7 +143,7 @@ private boolean newGraphNotNeeded(final StaplerRequest req,
       return req.checkIfModified(t, rsp);
    }
 
-   @POST
+    // @org.kohsuke.stapler.verb.POST // POST blocks rendering in groovy defined web page
    public void doGraphMap(final StaplerRequest req,
            StaplerResponse rsp) throws IOException {
       if (newGraphNotNeeded(req, rsp)) {