docs(issue-template): Add note about prioritization (#17590)

Add a `<sub>` text at the end of the issue like [seen
here](https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/.github/ISSUE_TEMPLATE/bug_report.md).
We are using the issue form syntax, so it's added as pre-filled content.

Author: s1gr1d

.github/ISSUE_TEMPLATE/bug.yml

@@ -133,6 +133,16 @@ body:
       description: Logs? Screenshots? Yes, please.
     validations:
       required: true
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional Context
+      description:
+        Add any other context here. Please keep the pre-filled text, which helps us manage issue prioritization.
+      value: |-
+        <sub>Tip: React with 👍 to help prioritize this issue. Please use comments to provide useful context, avoiding `+1` or `me too`, to help us triage it.</sub>
+    validations:
+      required: false
   - type: markdown
     attributes:
       value: |-

.github/ISSUE_TEMPLATE/feature.yml

@@ -23,6 +23,16 @@ body:
         Add a blender to Sentry.
     validations:
       required: true
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional Context
+      description:
+        Add any other context here. Please keep the pre-filled text, which helps us manage feature prioritization.
+      value: |-
+        <sub>Tip: React with 👍 to help prioritize this improvement. Please use comments to provide useful context, avoiding `+1` or `me too`, to help us triage it.</sub>
+    validations:
+      required: false
   - type: markdown
     attributes:
       value: |-