Don't run core actions on forks (#11072)

.github/workflows/announce-lts-rc.yml

@@ -7,6 +7,7 @@ on:
 jobs:
   post:
     runs-on: ubuntu-latest
+    if: ${{ github.repository_owner == 'jenkinsci' }}
     steps:
       - name: Post on Discourse
         uses: roots/discourse-topic-github-release-action@c30dc233349b7c6f24f52fb1c659cc64f13b5474 # v1.0.1

.github/workflows/changelog.yml

@@ -18,7 +18,7 @@ jobs:
       pull-requests: write # to add label to PR (release-drafter/release-drafter)
       contents: write # to create a github release (release-drafter/release-drafter)
 
-    if: github.repository_owner == 'jenkinsci'
+    if: ${{ github.repository_owner == 'jenkinsci' }}
     runs-on: ubuntu-latest
     steps:
       # Drafts your next Release notes as Pull Requests are merged into "master"

.github/workflows/label-conflicting-pr.yml

@@ -9,7 +9,7 @@ permissions:
 
 jobs:
   main:
-    if: github.event.pull_request.user.login != 'dependabot[bot]'
+    if: ${{ github.event.pull_request.user.login != 'dependabot[bot]' && github.repository_owner == 'jenkinsci' }}
     runs-on: ubuntu-latest
     steps:
       - name: Label conflicting PRs

.github/workflows/publish-release-artifact.yml

@@ -9,6 +9,7 @@ permissions:
 
 jobs:
   determine-version:
+    if: ${{ github.repository_owner == 'jenkinsci' }}
     runs-on: ubuntu-latest
     outputs:
       project-version: ${{ steps.set-version.outputs.project-version }}

.github/workflows/require-changelog-label.yml

@@ -6,6 +6,7 @@ on:
       - "master"
 jobs:
   label:
+    if: ${{ github.repository_owner == 'jenkinsci' }}
     runs-on: ubuntu-latest
     permissions:
       issues: write