Add issue template for doc issues (opensearch-project#4194)

* Add issue template for doc issues

Signed-off-by: Simeon Widdis <sawiddis@amazon.com>

* Fix indents

Signed-off-by: Simeon Widdis <sawiddis@amazon.com>

---------

Signed-off-by: Simeon Widdis <sawiddis@amazon.com>

Author: Swiddis

.github/ISSUE_TEMPLATE/docs-issue.md

@@ -0,0 +1,20 @@
+---
+name: 📃 Documentation issue
+about: Need docs? Create an issue to request or add new documentation.
+title: '[DOC]'
+labels: 'untriaged, documentation'
+assignees: ''
+---
+
+**What do you want to do?**
+
+- [ ] Request a change to existing documentation
+- [ ] Add new documentation
+- [ ] Report a technical problem with the documentation
+- [ ] Other
+  
+**Tell us about your request.** Provide a summary of the request.
+
+**Version:** List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.
+
+**What other resources are available?** Provide links to related issues, POCs, steps for testing, etc.