Update supported version in yaml test file for the primary_only parameter in force-merge API (opensearch-project#13279)

* Update supported version for the primary_only parameter in force-merge API

Signed-off-by: Gao Binlong <gbinlong@amazon.com>

* Update reason to make it consitent with 2.x

Signed-off-by: Gao Binlong <gbinlong@amazon.com>

---------

Signed-off-by: Gao Binlong <gbinlong@amazon.com>

Author: gaobinlong

rest-api-spec/src/main/resources/rest-api-spec/test/indices.forcemerge/10_basic.yml

@@ -31,8 +31,8 @@
 ---
 "Test primary_only parameter":
   - skip:
-      version: " - 2.99.99"
-      reason: "primary_only is available in 3.0+"
+      version: " - 2.12.99"
+      reason: "primary_only is available in 2.13.0+"
 
   - do:
       indices.create: