WithOsEnv assumes wrongly that os.Environ() returns only strings containing an equal sign #639
Description
https://github.com/compose-spec/compose-go/blob/main/cli/options.go#L240
This will call GetAsEqualsMap which will throw with an index out of bound in case a string does not contain an equal sign.
(we did hit that with a broken test in nerdctl - containerd/nerdctl#3111)