Forbid un-templated issues and add links

Adds links to GitHub Discussions and Slack instance.

.github/ISSUE_TEMPLATE/config.yaml

@@ -0,0 +1,25 @@
+---
+# Copyright The Enterprise Contract Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+blank_issues_enabled: false
+contact_links:
+  - name: Community Forum
+    url: https://github.com/enterprise-contract/ec-cli/discussions
+    about: Please ask and answer questions here.
+  - name: Community Chat
+    url: https://join.slack.com/t/enterprisecontract/shared_invite/zt-26l68e6wj-apw7c55CsDtd6Q9TgtiGuw
+    about: Chat with the community