Fix Config Validation

[darrenfu]

== RELEASE NOTES ==

General Changes
* Fix config validation. Based on JSR 303, validation should be applied on getter methods only. This fix will move all setter-side javax validation annotations to getter methods. This applies to all three Config Bean files.

Reference:

• JSR 303 official link
• JSR 303 bean validation - Why on getter and not setter discussion link
• Errors without this fix

Similar PR as the one applied to 0.228: #16162

[darrenfu]

Thanks for approval @arhimondr
I would like to see this PR included in release 0.255.