Change Support Request template to a link to Slack (#10480)

* Change Support Request template to a link to Slack

* Update .github/ISSUE_TEMPLATE/config.yml

Co-authored-by: Kaxil Naik <kaxilnaik@gmail.com>

Co-authored-by: Kaxil Naik <kaxilnaik@gmail.com>

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Ask a question or get support
+    url: https://s.apache.org/airflow-slack
+    about: Ask a question or request support for using Apache Airflow

.github/ISSUE_TEMPLATE/support_request.md

@@ -1,14 +0,0 @@
----
-name: Question or Support request
-about: Any questions you might have.
-title: ''
-labels: invalid
-assignees: ''
-
----
-
-**Do not use issues for support requests or general help queries**
-
-Please ask on one of our mailing lists, or in our Slack channel. See the "Ask a question" section of http://airflow.apache.org/community/
-
-Issues which are not bug reports or feature requests (i.e. "how do I get X working", or "How do I best do X?") will likely be closed without a response.