feature: add helm dependencies update

[Simperfit]

No description provided.

[teohhanhui]

https://docs.helm.sh/helm/#helm-dependency-update

On successful update, this will generate a lock file that can be used to rebuild the requirements to an exact version.

Shouldn't we check in the requirements.lock file? The command to use then becomes helm dependency build.

[teohhanhui]

Actually we should also do helm repo update before that? (I'm not sure.)

[dunglas]

Thanks @Simperfit. I think we need to add the lock file, indeed.

[teohhanhui]

@dunglas The requirements.lock file has been added in api-platform/api-platform#666

[dunglas]

Do we need to update the docs then?

[teohhanhui]

It depends on whether we think it's desirable to have fixed dependencies. I'm not sure it's the right thing to do.