Bump `globalprotect-openconnect` to `2.3.9` #16077

Job	Run time
get-merge-commit / resolve-merge-commit	7s
Attributes	1m 7s
Eval nixpkgs with aliases enabled	36s
Outpaths (aarch64-linux)	3m 46s
Outpaths (aarch64-darwin)	3m 28s
Outpaths (x86_64-linux)	3m 57s
Outpaths (x86_64-darwin)	3m 34s
Process	1m 19s
Tag	6s
	18m 0s

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