ci: test-kata-deploy: Get rid of slash-command-action action

There is a problem with slash-command-action which is on absence of a slash command
the job fails (instead of simply ignore, i.e., skip). This is documented on
https://github.com/xt0rted/slash-command-action/issues/124. There is a workaround
also documented on that issue, but here instead let's get rid of the action.

In this new implementation all comments sent to the pull request are parsed, if any
starts with "/test_kata-deploy" then the job is triggered.

Fixes #2836
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>

.github/workflows/kata-deploy-test.yaml

@@ -5,26 +5,12 @@ on:
 name: test-kata-deploy
 
 jobs:
-  check_comments:
-    if: ${{ github.event.issue.pull_request }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Check for Command
-        id: command
-        uses: kata-containers/slash-command-action@v1
-        with:
-          repo-token: ${{ secrets.GITHUB_TOKEN }}
-          command: "test_kata_deploy"
-          reaction: "true"
-          reaction-type: "eyes"
-          allow-edits: "false"
-          permission-level: admin
-      - name: verify command arg is kata-deploy
-        run: |
-           echo "The command was '${{ steps.command.outputs.command-name }}' with arguments '${{ steps.command.outputs.command-arguments }}'"
-
   create-and-test-container:
-    needs: check_comments
+    if: |
+      github.event.issue.pull_request
+      && github.event_name == 'issue_comment'
+      && github.event.action == 'created'
+      && startsWith(github.event.comment.body, '/test_kata_deploy')
     runs-on: ubuntu-latest
     steps:
       - name: get-PR-ref