[BUG] Redundant `if` condition in the compose/build.go `toAPIBuildOptions` function

[kapurm17]

Description

There's a redundant validation for error in the toAPIBuildOptions function in the compose/build.go file.
The initialsed err is never allotted a value and is still being checked. We should be able to safely remove this check.

CodeSnippet:

func (opts buildOptions) toAPIBuildOptions(services []string) (api.BuildOptions, error) {
	var SSHKeys []types.SSHKey
	var err error
	if opts.ssh != "" {
		id, path, found := strings.Cut(opts.ssh, "=")
		if !found && id != "default" {
			return api.BuildOptions{}, fmt.Errorf("invalid ssh key %q", opts.ssh)
		}
		SSHKeys = append(SSHKeys, types.SSHKey{
			ID: id,
			Path: path,
		})
		if err != nil {
			return api.BuildOptions{}, err
		}
	}
	builderName := opts.builder
	if builderName == "" {
		builderName = os.Getenv("BUILDX_BUILDER")
	}

	uiMode := ui.Mode
	if uiMode == ui.ModeJSON {
		uiMode = "rawjson"
	}
	return api.BuildOptions{
		Pull: opts.pull,
		Push: opts.push,
		Progress: uiMode,
		Args: types.NewMappingWithEquals(opts.args),
		NoCache: opts.noCache,
		Quiet: opts.quiet,
		Services: services,
		Deps: opts.deps,
		SSHs: SSHKeys,
		Builder: builderName,
	}, nil
}

CodeRef : https://github.com/docker/compose/blob/main/cmd/compose/build.go#L61

Steps To Reproduce

NA

Compose Version

NA

Docker Environment

NA

Anything else?

No response

[kapurm17]

I was going through the codebase to start with my contributions here. I can pick this as a good first issue where I can build the codebase (and possibly go through it in depth) to validate the change, if this looks good.