[Enhancement]: prevent CRD deletion if their CRs still exist in cluster

[loveRhythm1990]

Is there an existing issue for enhancement?

• I have checked the existing issues.

What would you like to be added ?

If a CRD has been deleted, all its CRs will be deleted too, in most case this is not a problem, since CRD will not be deleted generally, but we should consider this problem when our CRD should updated, like change a CRD field

Why is this needed ?

No response

Additional information

No response

[loveRhythm1990]

currently helm crds directory is under templates directory, most likely crds will be viewed as common resources, so when we uninstall matrixone-operator by helm uninstall, these crds will be uninstalled. By helm doc, we know that, directory crds should be in same directory with templates, but there are advantages and disadvantages about helm implementation