[DOCS] Changed to link specifically to 6.0 branch.
[DOCS] Changed to link specifically to 6.0 branch.

Original commit: elastic/x-pack-elasticsearch@247fd4b909e91a3a82c798d735b025c03917b8a3

scorpionvicky/elasticsearch,GlenRSmith/elasticsearch,nknize/elasticsearch,GlenRSmith/elasticsearch,scorpionvicky/elasticsearch,gfyoung/elasticsearch,gingerwizard/elasticsearch,robin13/elasticsearch,uschindler/elasticsearch,scorpionvicky/elasticsearch,nknize/elasticsearch,robin13/elasticsearch,uschindler/elasticsearch,uschindler/elasticsearch,coding0011/elasticsearch,gfyoung/elasticsearch,gfyoung/elasticsearch,HonzaKral/elasticsearch,GlenRSmith/elasticsearch,scorpionvicky/elasticsearch,nknize/elasticsearch,coding0011/elasticsearch,coding0011/elasticsearch,HonzaKral/elasticsearch,HonzaKral/elasticsearch,gingerwizard/elasticsearch,coding0011/elasticsearch,robin13/elasticsearch,gingerwizard/elasticsearch,GlenRSmith/elasticsearch,gingerwizard/elasticsearch,scorpionvicky/elasticsearch,robin13/elasticsearch,coding0011/elasticsearch,gfyoung/elasticsearch,gfyoung/elasticsearch,gingerwizard/elasticsearch,gingerwizard/elasticsearch,nknize/elasticsearch,nknize/elasticsearch,robin13/elasticsearch,uschindler/elasticsearch,GlenRSmith/elasticsearch,gingerwizard/elasticsearch,uschindler/elasticsearch,HonzaKral/elasticsearch