Changes dropdown ESS release field to free-text in docs issue template (#6358)

* Adds more stack versions to docs issue template

* Changes dropdown to free-text field

Author: natasha-moore-elastic

.github/ISSUE_TEMPLATE/docs-request-internal.yaml

@@ -44,19 +44,14 @@ body:
       default: 0
     validations:
       required: true
-  - type: dropdown
+  - type: textarea
     id: version-ess
     attributes:
       label: ESS release
-      description: Select a release version if your request is tied to the Elastic Stack release schedule.
-      options:
-        - '8.12'
-        - '8.13'
-        - '8.14'
-        - '8.15'
-        - '8.16'
-        - 'N/A'
-      default: 0
+      description: Please provide a release version if your request is tied to the Elastic Stack release schedule.
+      placeholder: |
+        For example:
+        "The functionality is being introduced in ESS version 8.18.0"
     validations:
       required: true
   - type: input