Remove useless api sample template files for flavor-rxtx v3

flavor-rxtx template files flavor-get-resp.* and flavors-detail-resp.*
isn't used by any api sample test. So remove them.

Change-Id: I74760bcd5367487aca31cdf94fa5e5715f19f4c6
Merge "Remove useless api sample template files for flavor-rxtx v3"