doc: Add issue templates for example and test, and update the contribution guidelines and PR templates with corresponding examples

.github/ISSUE_TEMPLATE/ex.yml

@@ -0,0 +1,29 @@
+name: Report an issue with an example
+description: Add or enhance examples.
+labels: [ 'example' ]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for helping us update our example!
+  - type: textarea
+    id: example_description
+    attributes:
+      label: Example Description
+      description: The specific details of the example.
+    validations:
+      required: true
+  - type: textarea
+    id: rationale
+    attributes:
+      label: Rationale
+      description: What problem does this example solve?
+    validations:
+      required: true
+  - type: textarea
+    id: additional_information
+    attributes:
+      label: Additional Information
+      description: What additional information do you need to provide?
+    validations:
+      required: false

.github/ISSUE_TEMPLATE/test.yml

@@ -0,0 +1,29 @@
+name: Report an issue with an test
+description: Add or improve tests.
+labels: [ 'test' ]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for helping us update our test!
+  - type: textarea
+    id: test_description
+    attributes:
+      label: Test Description
+      description: The specific details of the test.
+    validations:
+      required: true
+  - type: textarea
+    id: rationale
+    attributes:
+      label: Rationale
+      description: What problem does this test solve?
+    validations:
+      required: true
+  - type: textarea
+    id: additional_information
+    attributes:
+      label: Additional Information
+      description: What additional information do you need to provide?
+    validations:
+      required: false

.github/pull_request_template.md

@@ -26,6 +26,9 @@ Please delete options that are not relevant:
 - [ ] Bug fix
 - [ ] New feature
 - [ ] Documentation update
+- [ ] Add or improve tests
+- [ ] Add or enhance examples
+- [ ] Miscellaneous tasks
 - [ ] Other (please describe):
 
 ## How Has This Been Tested?

CONTRIBUTING.md

@@ -61,6 +61,8 @@ Do note that our [Code of Conduct](CODE_OF_CONDUCT.md) applies to all Katharsis
 | documentation | doc    |
 | enhancement   | feat   |
 | bug           | fix    |
+| example       | ex     |
+| test          | test   |
 | chore         | chore  |
 
 Format: `<branch prefix>/<branch content>`