Remove [compute-feature-enabled] vnc_server_header

This option was deprecated some years back[1], and has had no effect
since the 22.0.0 release.

[1] fd01d15d144caa4d5a482301d05cf724c75c4500

Change-Id: Ib2ac35eec958153e139f2fcfee05c2d6aeb56e81
2 files changed