docs: update issue template with contribution details (#379)

Signed-off-by: Sertac Ozercan <sozercan@gmail.com>

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -1,7 +1,8 @@
 name: Bug Report
 description: Report a bug in Project Copacetic
 title: "[BUG] <title>"
-labels: "bug"
+labels:
+  - "bug"
 body:
   - type: markdown
     attributes:
@@ -32,4 +33,11 @@ body:
   - type: markdown
     attributes:
       value: |
-        Thanks for taking the time to fill out a bug report! 
+        Thanks for taking the time to fill out a bug report!
+  - type: checkboxes
+    id: idea
+    attributes:
+      label: "Are you willing to submit PRs to contribute to this bug fix?"
+      description: "This is absolutely not required, but we are happy to guide you in the contribution process especially when you already have a good proposal or understanding of how to implement it. Join us at the `#copa` channel on the [OCI Slack](https://communityinviter.com/apps/opencontainers/join-the-oci-community) if you have any questions."
+      options:
+        - label: Yes, I am willing to implement it.

.github/ISSUE_TEMPLATE/documentation.yml

@@ -1,7 +1,8 @@
 name: Documentation Improvement
 description: Suggest a correction or improvement in Project Copacetic documents
 title: "[DOC] <title>"
-labels: "documentation"
+labels:
+  - "documentation"
 body:
   - type: markdown
     attributes:
@@ -25,4 +26,11 @@ body:
   - type: markdown
     attributes:
       value: |
-        Thanks for taking the time to suggest a documentation improvement! 
+        Thanks for taking the time to suggest a documentation improvement!
+  - type: checkboxes
+    id: idea
+    attributes:
+      label: "Are you willing to submit PRs to contribute to documentation?"
+      description: "This is absolutely not required, but we are happy to guide you in the contribution process. Join us at the `#copa` channel on the [OCI Slack](https://communityinviter.com/apps/opencontainers/join-the-oci-community) if you have any questions."
+      options:
+        - label: Yes, I am willing to implement it.

.github/ISSUE_TEMPLATE/question.yml

@@ -1,7 +1,8 @@
 name: Question
 description: Ask a question about Project Copacetic
 title: "[QUESTION] <title>"
-labels: "question"
+labels:
+  - "question"
 body:
   - type: markdown
     attributes:

.github/ISSUE_TEMPLATE/request.yml

@@ -1,7 +1,8 @@
 name: Request
 description: Request a new feature or propose an enhancement to Project Copacetic
 title: "[REQ] <title>"
-labels: "enhancement"
+labels:
+  - "enhancement"
 body:
   - type: markdown
     attributes:
@@ -20,8 +21,15 @@ body:
       label: What is your request or suggestion?
       placeholder: |
         e.g. I would like copa to add this <feature> so that I can use it in my <scenario>.
-        e.g. When using <copa command> the <current behavior> has this <limitation> and it would be better if it has this <improvement>. 
+        e.g. When using <copa command> the <current behavior> has this <limitation> and it would be better if it has this <improvement>.
   - type: markdown
     attributes:
       value: |
-        Thanks for taking the time to fill out a request! 
+        Thanks for taking the time to fill out a request!
+  - type: checkboxes
+    id: idea
+    attributes:
+      label: "Are you willing to submit PRs to contribute to this feature request?"
+      description: "This is absolutely not required, but we are happy to guide you in the contribution process especially when you already have a good proposal or understanding of how to implement it. Join us at the `#copa` channel on the [OCI Slack](https://communityinviter.com/apps/opencontainers/join-the-oci-community) if you have any questions."
+      options:
+        - label: Yes, I am willing to implement it.