Use zuul-providers for nodesets in opendev/zuul tenants

Switch the opendev and zuul tenants to load their nodesets from
the zuul-providers repo, so that it controls whether we use
nodepool or niz nodes.

Depends-On: https://review.opendev.org/c/opendev/zuul-providers/+/947606
Change-Id: I4da91d239b0958ae1ec89e94f76300b4e2f264d4

zuul/main.yaml

@@ -23,7 +23,8 @@
       gerrit:
         config-projects:
           - opendev/project-config
-          - opendev/base-jobs
+          - opendev/base-jobs:
+              exclude: nodeset
         untrusted-projects:
           - zuul/zuul-jobs
           - inaugust/inaugust.com
@@ -40,7 +41,7 @@
               # to the experimental config objects.
               include:
                 - job
-                # - nodeset
+                - nodeset
                 - secret
                 - project
                 - project-template
@@ -1549,7 +1550,6 @@
               include:
                 - job
                 - secret
-                - nodeset
           - zuul/zuul-base-jobs:
               extra-config-paths:
                 - zuul-tests.d/