[DOCS] Fix typo
Original commit: elastic/x-pack-elasticsearch@7e6c42307f92d55559cf96dc934256952b5a1d13
directly to configure and access {xpack} features.
* <<info-api, Info API>>
-* Graph <<graph-explore-api, Explore API>>
+* <<graph-explore-api, Graph Explore API>>
* <<ml-apis, Machine Learning APIs>>
* <<security-api,Security APIs>>
* <<watcher-api, Watcher APIs>>
