Create Secrets Manager discussion template (#5129)

.github/DISCUSSION_TEMPLATE/secrets-manager.yml

@@ -0,0 +1,11 @@
+body:
+  - type: markdown
+    attributes:
+      value: |
+        If you would like to contribute code to the Bitwarden codebase for consideration, please review [https://contributing.bitwarden.com/](https://contributing.bitwarden.com/) before posting. To keep discussion on topic, posts that do not include a proposal for a code contribution you wish to develop will be removed. For feature requests and community discussion, please visit https://community.bitwarden.com/
+  - type: textarea
+    attributes:
+      label: Code Contribution Proposal
+      description: "Please include a description of the code contribution you would like to contribute, including any relevant screenshots, and links to any existing [feature requests](https://community.bitwarden.com/c/feature-requests/5/none). This helps get feedback from the community and Bitwarden team members before you start writing code"
+    validations:
+      required: true