feat: make PXC backup job resources configurable

[Harishrs2006]

Fixes: #1905

Large (1TB+) PXC backups fail after ~5 hours because the xtrabackup
container has a hardcoded 600m CPU limit that cannot be overridden by users.

Related pull requests
Will be linked from openeverest/openeverest once that PR is opened.

Cause:
genPXCStorageSpec() in applier.go hardcodes 600m CPU / 1G memory for
every BackupStorageSpec.Resources with no way to override it from user input.

Solution:
Added BackupJobResources *Resources field to DatabaseClusterBackupSpec.
When set, the values override the defaults in getStoragesSpec() before
the BackupStorageSpec is passed to the PXC operator.

[atharvamhaske]

again ai slop

[atharvamhaske]

Fixes: #1905

Large (1TB+) PXC backups fail after ~5 hours because the xtrabackup container has a hardcoded 600m CPU limit that cannot be overridden by users.

Related pull requests Will be linked from openeverest/openeverest once that PR is opened.

• [link]

Cause: genPXCStorageSpec() in applier.go hardcodes 600m CPU / 1G memory for every BackupStorageSpec.Resources with no way to override it from user input.

Solution: Added BackupJobResources *Resources field to DatabaseClusterBackupSpec. When set, the values override the defaults in getStoragesSpec() before the BackupStorageSpec is passed to the PXC operator.

where is your link bro? are you even checking before raising issues or PR?

[Harishrs2006]

@atharvamhaske
sorry, that was an unfilled placeholder i missed.
i have removed it from the description.