Use patchSetInserter.disableValidation() when importing pull-requests

The master branch removed the patchSetInserter.setValidate(false)
in favour of batter named patchSetInserter.disableValidation().

Change-Id: I1c808eeee503f53a20640470f0b0351c054b09fa

github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/git/PullRequestCreateChange.java

diff --git a/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/git/PullRequestCreateChange.java b/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/git/PullRequestCreateChange.java
index d1554c3..e69b118 100644
--- a/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/git/PullRequestCreateChange.java
+++ b/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/git/PullRequestCreateChange.java
@@ -233,7 +233,7 @@
       PatchSetInserter patchSetInserter =
           patchSetInserterFactory.create(changeNotes, psId, cherryPickCommit);
       patchSetInserter.setMessage(pullRequestMessage);
-      patchSetInserter.setValidate(false);
+      patchSetInserter.disableValidation();
 
       bu.addOp(change.getId(), patchSetInserter);
       bu.execute();