Adds main branch to eland repo to docs build (#2212)

Co-authored-by: István Zoltán Szabó <[email protected]>

Author: sethmlarson

conf.yaml

@@ -580,9 +580,9 @@ contents:
                     path:   docs/guide/
               - title:      eland
                 prefix:     eland
-                current:    master
-                branches:   [ master ]
-                live:       [ master ]
+                current:    main
+                branches:   [ {main: master} ]
+                live:       [ main ]
                 index:      docs/guide/index.asciidoc
                 chunk:     1
                 tags:       Clients/eland