GitHub issue templates (LuaLS#2796)

* add: documentation template

* add: issue template config

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Report LuaLS.github.io issues
+    url: https://github.com/LuaLS/LuaLS.github.io/issues
+    about: Please report issues regarding our website (and the documentation on it) in the website repository.

.github/ISSUE_TEMPLATE/doc-report.yml

@@ -0,0 +1,34 @@
+name: Documentation Report
+description: Report an issue with documentation in the lua-language-server.
+labels:
+  - documentation
+assignees:
+  - carsakiller
+body:
+  - type: markdown
+    attributes:
+      value: >
+        For issues with our [website](https://luals.github.io) and its wiki,
+        please visit the [correct repository](https://github.com/LuaLS/LuaLS.github.io/issues).
+  - type: markdown
+    attributes:
+      value: >
+        **Please check for similar issues before continuing!**
+  - type: textarea
+    id: expected
+    attributes:
+      label: Issue Description
+      description: Please describe the documentation issue. Is something incorrect, missing or improveable?
+    validations:
+      required: true
+  - type: textarea
+    id: additional-notes
+    attributes:
+      label: Additional Notes
+      description: >
+        Please provide any additional notes, context,
+        and media you have.
+  - type: markdown
+    attributes:
+      value: |
+        Thank you very much for helping improve the language server! ❤️