fix: ovn snat and fip delete

[ShaPoHun]

• Make sure you have followed Kube-OVN Code Style.

What type of this PR

Examples of user facing changes:

• Bug fixes
  If fip or snat is not ready, fip or snat cannot be deleted

[github-actions]

• The commit message should be more descriptive and informative. It should explain what the patch does and why it is necessary.
• There are some typos in the code comments, such as "delte" instead of "delete".
• In both ovn_fip.go and ovn_snat.go, there is a potential bug where the cachedFip.Status.Ready or cachedSnat.Status.Ready condition may not be sufficient to ensure that the FIP or SNAT rule exists before attempting to delete it. It would be better to check for the existence of the rule explicitly before attempting to delete it.
• There are some formatting errors in the code, such as inconsistent indentation and spacing. These should be fixed to improve readability.
• There are no obvious performance issues or ways to improve the code.

[github-actions]

• The commit message is missing. It should provide a brief description of the changes made in the patch.
• There are no potential bugs or format errors in the code patch diff.
• There are no performance issues in the code patch diff.
• In handleAddOvnDnatRule and handleAddOvnFip, there is a new call to patchOvnDnatStatus and patchOvnFipStatus respectively, but it is not clear what this function does. It would be helpful to add comments explaining the purpose of these functions.
• In handleAddOvnSnatRule, there is a new call to patchOvnSnatStatus, but it is not clear what this function does. It would be helpful to add comments explaining the purpose of this function.
• In handleDelOvnDnatRule, handleDelOvnFip, and handleUpdateOvnSnatRule, there is a check for cachedDnat.Status.Ready, cachedFip.Status.Vpc != "" && cachedFip.Status.V4Eip != "" && cachedFip.Status.V4Ip != "", and cachedSnat.Status.Vpc != "" && cachedSnat.Status.V4Eip != "" && cachedSnat.Status.V4IpCidr != "" respectively. It is not clear why these checks are necessary and what they are trying to achieve. It would be helpful to add comments explaining the purpose of these checks.
• In handleDelOvnDnatRule, handleDelOvnFip, and handleUpdateOvnSnatRule, there is a call to klog.Errorf with the message "failed to delete dnat/fip/snat, %v". The error message should be more specific and provide more information about the error that occurred.