meta: convert workflow file to GitHub Actions v2 yml syntax

.github/main.workflow

-workflow "Triage Pull Request" {
-  on = "pull_request"
-  resolves = ["Triage"]
-}
-
-# Only act if there are code changes: if the pull_request
-# event's action is either 'opened' (new PR) or 'synchronize' (new commits)
-action "Filter actions" {
-  uses = "actions/bin/filter@0ac6d44"
-  args = "action 'opened|synchronize'"
-}
-
-action "Triage" {
-  needs = ["Filter actions"]
-  uses = "ohmyzsh/github-actions/pull-request-triage@master"
-  secrets = ["GITHUB_TOKEN"]
-}

.github/workflows/pull_request_triage.yml

+on: pull_request
+name: Triage Pull Request
+jobs:
+  mainJob:
+    name: Triage
+    if: github.event.action == 'opened' || github.event.action == 'synchronize'
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@master
+    - name: Analyze and triage
+      uses: ohmyzsh/github-actions/pull-request-triage@master
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}