chore: Add labeler action to automate PR labeling (#1298)

Signed-off-by: Marco Kilchhofer <mkilchhofer@users.noreply.github.com>

.github/configs/labeler.yaml

@@ -0,0 +1,14 @@
+argo-cd:
+  - charts/argo-cd/**/*
+
+argo-events:
+  - charts/argo-events/**/*
+
+argo-rollouts:
+  - charts/argo-rollouts/**/*
+
+argo-workflows:
+  - charts/argo-workflows/**/*
+
+argocd-image-updater:
+  - charts/argocd-image-updater/**/*

.github/workflows/pr-sizing.yml

@@ -1,14 +1,28 @@
 ## Reference: https://github.com/pascalgn/size-label-action
 ---
-name: 'PR Size'
+name: 'PR Labeling'
 on: 
   pull_request_target:
     types: [opened, synchronize, reopened]
+
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
+  triage:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/labeler@v4
+        with:
+          configuration-path: ".github/configs/labeler.yaml"
+          repo-token: "${{ secrets.GITHUB_TOKEN }}"
+          sync-labels: true
+
   size-label:
     runs-on: ubuntu-latest
     steps:
       - name: size-label
         uses: "pascalgn/size-label-action@v0.4.2"
         env:
-          GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+          GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"