reprioritize gate and check queues

Bump check queue to normal priority so that it will get resources
before merge-check or silent queues. Same for triple-o check, for same
reasons.

Bump gate queue to high priority to keep it ahead of the check
queue. It was brought back down to normal previously because it was
starving release jobs, however with the new sliding window on the gate
we effectively cap gate capacity, and this shouldn't be an actual
issue.

Change-Id: I7430c7293ad843a405d321d987c9dfaf7b4ab364

zuul/layout.yaml

@@ -7,7 +7,7 @@ pipelines:
     failure-message: Build failed.  For information on how to proceed, see https://wiki.openstack.org/wiki/GerritJenkinsGit#Test_Failures
     manager: IndependentPipelineManager
     source: gerrit
-    precedence: low
+    precedence: normal
     require:
       open: True
       current-patchset: True
@@ -35,7 +35,7 @@ pipelines:
     failure-message: Build failed.  For information on how to proceed, see https://wiki.openstack.org/wiki/GerritJenkinsGit#Test_Failures
     manager: DependentPipelineManager
     source: gerrit
-    precedence: normal
+    precedence: high
     require:
       open: True
       current-patchset: True
@@ -180,7 +180,7 @@ pipelines:
       https://wiki.openstack.org/wiki/GerritJenkinsGit#Test_Failures
     manager: IndependentPipelineManager
     source: gerrit
-    precedence: low
+    precedence: normal
     require:
       open: True
       current-patchset: True