doc: fix deprecation entry formatting (DEP0206)

Author: Anshikakalpana

doc/api/deprecations.md

@@ -4564,7 +4564,7 @@ removed in a future version of Node.js.
 changes:
   - version: REPLACEME
     pr-url: https://github.com/nodejs/node/pull/XXXXX
-    description: Runtime-deprecation.
+    description: Runtime deprecation.
 -->
 
 Type: Runtime