Build: only build on OSS for main/version (#46079)

* Only do main/version builds on OSS repo

* Sign drone

Co-authored-by: Dimitris Sotirakis <sotirakis.dim@gmail.com>

scripts/drone/pipelines/main.star

@@ -190,6 +190,9 @@ def main_pipelines(edition):
     trigger = {
         'event': ['push',],
         'branch': 'main',
+        'repo': [
+          'grafana/grafana',
+        ],
     }
     drone_change_trigger = {
         'event': ['push',],

scripts/drone/version.star

@@ -8,4 +8,7 @@ ver_mode = 'release-branch'
 def version_branch_pipelines():
     return release_pipelines(ver_mode=ver_mode, trigger={
         'ref': ['refs/heads/v[0-9]*'],
+        'repo': [
+          'grafana/grafana',
+        ],
     })