[repo] Change Markdown issue templates to YAML (#5595)

Author: reyang

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,34 @@
+name: Feature request
+description: Suggest an idea for this project
+labels: ["enhancement"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this feature request! Please make sure to fill out the entire form below, providing as much context as you can in order to help us triage and track down your request as quickly as possible.
+
+        Before opening a feature request, consider whether the feature should/could be implemented in the [other OpenTelemetry client libraries](https://github.com/open-telemetry/). If so, please [open an issue on opentelemetry-specification](https://github.com/open-telemetry/opentelemetry-specification/issues/new) first.
+
+  - type: textarea
+    attributes:
+      label: Is your feature request related to a problem?
+      description: If so, provide a concise description of the problem.
+
+  - type: textarea
+    attributes:
+      label: What is the expected behavior?
+      description: Describe the solution you would like.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Which alternative solutions or features have you considered?
+      description: Describe alternatives you've considered.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Additional context
+      description: Any additional information you think may be relevant to this feature request.

.github/ISSUE_TEMPLATE/feature_request.yaml

@@ -0,0 +1,21 @@
+name: Question
+description: Ask a question to help us improve our knowledge base and documentation
+labels: ["question"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        > [!NOTE]
+        > Please ask questions using [GitHub Discussions](https://github.com/open-telemetry/opentelemetry-dotnet/discussions/new) instead of GitHub Issues.
+
+  - type: textarea
+    attributes:
+      label: What is the question?
+      description: Describe the question you have.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Additional context
+      description: Any additional information you think may be relevant to this question.