Revert "Mute "tsdb" yaml test (#78599)" (#78603)

This reverts commit abdf8fe248542ee34008bfb35893badb51e7a517.

qa/multi-cluster-search/src/test/resources/rest-api-spec/test/remote_cluster/10_basic.yml

@@ -156,8 +156,8 @@
 ---
 tsdb:
   - skip:
-      version: "all"
-      reason: "AwaitsFix https://github.com/elastic/elasticsearch/issues/78598"
+      version: " - 7.99.99"
+      reason: introduced in 8.0.0
 
   - do:
       indices.create: