fix(gnss_launch): remove gnss_frame arg

[KYabuuchi]

Description

I removed gnss_frame arg.

gnns_poser refers to msg.header.frame_id instead of parameter gnss_frame.
Please see autowarefoundation/autoware_universe#6116

(The original reason why we can not pass gnss_frame as arg is autowarefoundation/autoware_universe#5140 )

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