test: reduce unimportant feature combinations

Test time reduces from 1m15s to 29.75s

Disk usage reduces from 18.5GB to 7.5GB

Author: KSXGitHub

test.sh

@@ -76,10 +76,6 @@ unit "$@"
 unit --no-default-features "$@"
 unit --all-features "$@"
 unit --features cli "$@"
-unit --features cli-completions "$@"
-unit --features man-page "$@"
-unit --features usage-md "$@"
-unit --features ai-instructions "$@"
 
 if [[ -f "$failure_marker" ]]; then
   echo >&2