Upgrade markdown templates to issue forms (#2588)

.github/ISSUE_TEMPLATE/bug-report.yml

@@ -0,0 +1,66 @@
+name: 🐞 Bug report
+description: Create a report to help us improve
+labels: ["bug", "triage"]
+body:
+  - type: checkboxes
+    id: existing
+    attributes:
+      label: Is there an existing issue for this?
+      description: Please search to see if an issue already exists for the bug you encountered.
+      options:
+      - label: I have searched the existing issues
+        required: true
+  - type: textarea
+    id: description
+    attributes:
+      label: Describe the bug
+      description: A clear and concise description of what the bug is, make sure to paste any exceptions and tracebacks using markdown code-block syntax to make it easier to read.
+    validations:
+      required: true
+  - type: textarea
+    id: code
+    attributes:
+      label: Code snippet
+      description: Relevant source code, make sure to remove what is not necessary.
+    validations:
+      required: false
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected Behavior
+      description: A concise description of what you expected to happen.
+    validations:
+      required: false
+  - type: dropdown
+    id: running
+    attributes:
+      label: How do you run Sanic?
+      options:
+        - Sanic CLI
+        - As a module
+        - As a script (`app.run` or `Sanic.serve`)
+        - ASGI
+    validations:
+      required: true
+  - type: input
+    id: os
+    attributes:
+      label: Operating System
+      description: What OS?
+    validations:
+      required: true
+  - type: input
+    id: version
+    attributes:
+      label: Sanic Version
+      description: Check startup logs or try `sanic --version`
+    validations:
+      required: true
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional context
+      description: Add any other context about the problem here.
+    validations:
+      required: false
+