"Conserved charges" of the Bondi-Metzner-Sachs algebra in the Brans-Dicke theory *Supported by the National Natural Science Foundation of China (11633001, 11920101003), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB23000000). This was also a project funded by China Postdoctoral Science Foundation (2020M672400). (February 2021)