v6.1.0

Symbolics v6.1.0

Diff since v6.0.0

Merged pull requests:

• Refactor: Remove redundant dependencies (#1212) (@bowenszhu)
• Use Symbolics v6 in downstream (#1213) (@ChrisRackauckas)
• Move ForwardDiff from [deps] to [weakdeps] to reduce load time (#1217) (@bowenszhu)
• add promote between BigFloat and Num (#1218) (@oscardssmith)
• Add sorting option to get_variables function (#1219) (@bowenszhu)

Closed issues:

• get_variables order (#1182)
• Registering Functions with mixed array/non-array types (#1188)