
Newer versions of PyYAML have removed the ability to rely on yaml.load() without passing an explicit Loader class. Instead, switch to its safe_load() function which has an implicit one. The same thing was done to our check_irc_access.py script in I72776774eabd4e397ee5e8bdd58b3632be8fd3a1 but we never updated accessbot similarly. Change-Id: I32370e35c908acc3b75326a8ac5cadc25ef0760f