Revert "Add CLA check GitHub action (#6479)"

This reverts commit 8eb8643a3a.

.github/workflows/main.yml

@@ -1,16 +0,0 @@
-on:
-  pull_request:
-    types: [opened]
-
-jobs:
-  cla-checker:
-    runs-on: ubuntu-latest
-    name: "Check CLA"
-    steps:
-      - name: "Lookup PR Author"
-        uses: influxdata/clasee@v1
-        with:
-          spreadsheet: "1jnRZYSw83oa6hcEBb1lxK6nNvXrWnOzPT8Bz9iR4Q8s"
-          range: "Form Responses!E:E"
-        env:
-          CLASEE_SECRET: ${{ secrets.CLASEE_SECRET }}