Remove greetings

.github/workflows/greetings.yml

@@ -1,13 +0,0 @@
-name: Greetings
-
-on: [pull_request, issues]
-
-jobs:
-  greeting:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/first-interaction@v1
-      with:
-        repo-token: ${{ secrets.GITHUB_TOKEN }}
-        issue-message: 'Thanks for your first issue!'
-        pr-message: 'Thanks for your first pr!'