Gitsync fails to read new credentials when using ESO Github token generator

### Description

We use Github for our git repos.

To provide access from airflow we use External Secrets Operator to manage this using GithubAccessToken that uses a github app to create the access token.
This token only lives for 1 hour maximum.
Because of this lifespan, The gitsync container needs to re-read the secret to have the new token.
Unfortunately it seems that gitsync doesn't support re-reading the secret while it's running.

This causes it to fail the sync, exit and restarts.
Thankfully it will restart fine and syncs again.

### Use case/motivation

Gitsync project have released a new feature https://github.com/kubernetes/git-sync/pull/976 that allows for reading a file that contains the password and re-read it at each sync loop

Env vars are only set at startup time so won't detect a change, therefor the secret will have to be mounted inside the container which I think should allow for accepting token rotations?

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

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