draft: feat: add MEILISEARCH_STORAGE_SIZE configuration

[viadanna]

Description

This PR makes it possible to configure MeiliSearch storage size.

Testing instructions

1. Create a new Tutor instance.
2. Modify the config.yml file, adding:

MEILISEARCH_STORAGE_SIZE: 1Gi

3. Run tutor k8s launch to deploy the new instance.
4. Confirm the deployment is successful.
5. Confirm the Meilisearch PVC new size:

$ kubectl -nsumac get pvc/meilisearch
NAME          STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   VOLUMEATTRIBUTESCLASS   AGE
meilisearch   Bound    pvc-6500a7bd--ee9211966da0   1Gi        RWO            gp2            <unset>                 20m

[xitij2000]

Looks good!

[regisb]

We are trying as much as we can to limit the number of Tutor configuration settings. In particular, we don't want to turn every hard-coded k8s value into a setting. Instead, operators should customise their environment using plugins. In this particular case, you should use the "k8s-override" patch.

For similar conversations, please look at:
#675
#677