Issue forms: replace enhancement request with form

Signed-off-by: Ekaterina Gerasimova <kittykat3756@gmail.com>

.github/ISSUE_TEMPLATE/enhancement.yml

@@ -0,0 +1,36 @@
+name: Enhancement request
+description: Do you have a suggestion or feature request?
+labels: [T-Enhancement]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for taking the time to propose a new feature or make a suggestion.
+  - type: textarea
+    id: usecase
+    attributes:
+      label: Your use case
+      description: What would you like to be able to do? Please feel welcome to include screenshots or mock ups.
+      placeholder: Tell us what you would like to do!
+      value: |
+        #### What would you like to do?
+
+        #### Why would you like to it?
+
+        #### How would you like to achieve it?
+    validations:
+      required: true
+  - type: textarea
+    id: alternative
+    attributes:
+      label: Have you considered any alternatives?
+      placeholder: A clear and concise description of any alternative solutions or features you've considered.
+    validations:
+      required: false
+  - type: textarea
+    id: additional-context
+    attributes:
+      label: Additional context
+      placeholder: Is there anything else you'd like to add?
+    validations:
+      required: false