chore(ci): remove semgrep workflow (#1644)

Signed-off-by: Pavel Boldyrev <627562+bpg@users.noreply.github.com>

.github/workflows/semgrep.yml

@@ -1,26 +0,0 @@
-name: Semgrep
-
-on:
-  pull_request: {}
-  push:
-    branches:
-      - main
-    paths:
-      - .github/workflows/semgrep.yml
-  schedule:
-    # random HH:MM to avoid a load spike on GitHub Actions at 00:00
-    - cron: 29 16 * * *
-
-jobs:
-  semgrep:
-    runs-on: ubuntu-latest
-    env:
-      SEMGREP_APP_TOKEN: "${{ secrets.SEMGREP_APP_TOKEN }}"
-    container:
-      image: returntocorp/semgrep
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Semgrep
-        run: semgrep ci