github: track issue with GitHub Project (#117)

It helps to track new issues by aggregating ones from Project view.

Signed-off-by: Kentaro Hayashi <hayashi@clear-code.com>

.github/workflows/add-to-project.yml

@@ -0,0 +1,17 @@
+name: Add bugs to fluent project
+
+on:
+  issues:
+    types:
+      - opened
+
+jobs:
+  add-to-project:
+    name: Add issue to project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/add-to-project@v1.0.2
+        with:
+          project-url: https://github.com/orgs/fluent/projects/4
+          github-token: ${{ secrets.ADD_TO_PROJECT_PAT }}
+          labeled: waiting-for-triage