[Chart] Fix rendering condition of "git_sync_ssh_key_volume"

[zezaeoh]

Issue

The pod-template-file.kubernetes-helm-yaml file provided as the default pod-template is missing a rendering condition for git_sync_ssh_key_volume when the SSH key is directly specified in the values (as opposed to using a secret reference).

Changes

This PR adds the missing condition to properly render the git sync SSH key volume in this use case.

[boring-cyborg]

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[potiuk]

@Miretpl -> WDYT ?

[Miretpl]

@potiuk approved

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.