Fix incorrect codegen for HttpApiKeyAuthTrait

[joewyz]

The current codegen for @httpApiKeyAuthTrait in client side missed a ) at the end of the assignment of in field and the enum Location in HttpApiKeyAuthTrait.java does not have a public from() method, which makes the generated HttpApiKeyAuthTrait invalid.
For the following trait:

@httpApiKeyAuth(name: "X-API-Key", in: "header")

The original generated code would be:

private static final HttpApiKeyAuthTrait httpApiKeyAuthScheme = HttpApiKeyAuthTrait.builder()
            .name("X-API-Key")
            .in(HttpApiKeyAuthTrait.Location.from("header")
            .build();

Generated code after fix:

private static final HttpApiKeyAuthTrait httpApiKeyAuthScheme = HttpApiKeyAuthTrait.builder()
            .name("X-Api-Key")
            .in(HttpApiKeyAuthTrait.Location.HEADER)
            .build();

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.