chore: configure some actions to be skipped for forks

.github/workflows/gh-actions-updater.yaml

@@ -7,6 +7,7 @@ on:
 
 jobs:
   build:
+    if: github.repository == 'juanfont/headscale'
     runs-on: ubuntu-latest
 
     steps:

.github/workflows/release.yml

@@ -9,6 +9,7 @@ on:
 
 jobs:
   goreleaser:
+    if: github.repository == 'juanfont/headscale'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout

.github/workflows/stale.yml

@@ -6,6 +6,7 @@ on:
 
 jobs:
   close-issues:
+    if: github.repository == 'juanfont/headscale'
     runs-on: ubuntu-latest
     permissions:
       issues: write

.github/workflows/update-flake.yml

@@ -6,6 +6,7 @@ on:
 
 jobs:
   lockfile:
+    if: github.repository == 'juanfont/headscale'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository