Change ghprbActualCommit and ghprbTargetBranch to main in all BML jobs

Change-Id: I22b221be261e2e80c1bda789cfe1d50489d086dc
diff --git a/jjb/metal3/job_bml_main_integration_tests.yml b/jjb/metal3/job_bml_main_integration_tests.yml
index a40174e..51c8f9c 100644
--- a/jjb/metal3/job_bml_main_integration_tests.yml
+++ b/jjb/metal3/job_bml_main_integration_tests.yml
@@ -44,7 +44,7 @@
         description: 'Project github repo name'
     - string:
         name: ghprbActualCommit
-        default: 'master'
+        default: 'main'
         description: 'CI Repo branch for triggering manual build'
     - string:
         name: ghprbAuthorRepoGitUrl
@@ -52,7 +52,7 @@
         description: 'CI Repo URL for triggering manual build'
     - string:
         name: ghprbTargetBranch
-        default: 'master'
+        default: 'main'
         description: 'Target branch of the PR'
     - string:
         name: IMAGE_OS