error trying to run echo bot example: seems like old package name is still used somewhere

[Simon-Laux]

go: echobot imports
	github.com/chatmail/rpc-client-go/deltachat: github.com/chatmail/rpc-client-go@v1.134.0: parsing go.mod:
	module declares its path as: github.com/deltachat/deltachat-rpc-client-go
	        but was required as: github.com/chatmail/rpc-client-go