Increase precision of bst_float values in tree dumps (#3298)
Increase precision of bst_float values in tree dumps (#3298)

* Increase precision of bst_float values in tree dumps

* Increase precision of bst_float values in tree dumps

* Fix lint error and switch precision to right float variable

* Fix clang-tidy error

dmlc/xgboost,dmlc/xgboost,dmlc/xgboost,dmlc/xgboost,dmlc/xgboost,dmlc/xgboost