Fix out of date template and grammar (#15483)

# Objective

A label was renamed, so this updates it in the issue template.

## Solution

Change in the .github markdown.

.github/ISSUE_TEMPLATE/docs_improvement.md

@@ -10,4 +10,4 @@ assignees: ''
 
 Provide a link to the documentation and describe how it could be improved. In what ways is it incomplete, incorrect, or misleading?
 
-If you have suggestions on exactly what the new docs should say, feel free to include them here. Or alternatively, make the changes yourself and [create a pull request](https://bevyengine.org/learn/book/contributing/code/) instead.
+If you have suggestions on exactly what the new docs should say, feel free to include them here. Alternatively, make the changes yourself and [create a pull request](https://bevyengine.org/learn/book/contributing/code/) instead.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -2,7 +2,7 @@
 name: Feature Request
 about: Propose a new feature!
 title: ''
-labels: C-Enhancement, S-Needs-Triage
+labels: C-Feature, S-Needs-Triage
 assignees: ''
 ---