[action] combine label and triage project add in one workflow

.github/workflows/labeler.yml

@@ -1,12 +0,0 @@
-name: Pull Request Labeler
-on:
-  pull_request_target
-
-jobs:
-  label:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/labeler@v3.0.2
-      with:
-        repo-token: "${{ secrets.GITHUB_TOKEN }}"
-

.github/workflows/triage.yml

@@ -0,0 +1,29 @@
+name: Add Issues and PRs to Triage
+
+on:
+  issues:
+    types:
+      - opened
+  pull_request_target:
+    types:
+      - opened
+
+jobs:
+
+  label:
+    name: Label PR
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request_target'
+    steps:
+    - uses: actions/labeler@v3.0.2
+      with:
+        repo-token: "${{ secrets.GITHUB_TOKEN }}"
+
+  add-to-project:
+    name: Add to Triage Project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/add-to-project@v0.3.0
+        with:
+          project-url: https://github.com/orgs/smallstep/projects/94
+          github-token: ${{ secrets.TRIAGE_PAT }}