Since https://github.com/spf13/cast/pull/269 / https://github.com/spf13/cast/commit/c6df2d85f953c415a56f3fe0d64e22f23f60b4a3, `ToStringMapString` returns nil if the input is empty. Before, in https://github.com/spf13/cast/blob/01004f2c354f73d3cb4651ad7360ad03fb588e79/caste.go#L1004 this would return an empty map. Is this breakage intentional? It is not documented and has caused https://github.com/evcc-io/evcc/issues/22267.