[global] Fix global services

[mikeland73]

Summary

cobra doesn't chain PersistentPreRunE. So if a parent declares one and a child declares it as well, the parent function is ignored. global uses PersistentPreRunE to set the global project directory. The services command was running it to ensure nix is installed. The child replaced the parent, so we were never setting th

The fix here is a bit ugly but it solves them problem.

There's a UX issue I rediscovered while testing this. When adding global packages the environment is not automatically refreshed. This means services wont work until a new shell is opened or if the user does eval "$(devbox global shellenv)" manually.

How was it tested?

devbox global add nginx
eval "$(devbox global shellenv)"
devbox global services up

[savil]

Instead of copy-pasting, it'll be nice to use a common variable...

persistentPreRunE := setGlobalConfigForDelegatedCommands(globalCmd)

*globalCmd = cobra.Command{
 		Use:   "global",
 		PersistentPreRunE: persistentPreRunE,
 		 ...
 		 }
 		 
 		 ...
 addCommandAndHideConfigFlag(
 		 globalCmd,
 		servicesCmd(persistentPreRunE),
 ),