Can't change Attribute generic.maxHealth for tamed wolves/dogs

The bug

After changing a tamed wolf's max health with the command: 

/data merge entity @e[type=wolf,limit=1,sort=nearest] {Health:10.0f,Attributes:[{Base:10.0d,Name:generic.maxHealth}]}

stays at 20.0d when checking with data get command and also dies after getting 20 damage, not 10.