Add kotlin-spring beanValidation for RequestBody parameters

[lukbaran]

Duplicated changes from #13932 to fix #16738.

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[wing328]

thanks for the PR. Tested locally to confirm the fix:

--- a/src/main/kotlin/org/openapitools/api/AddApiController.kt
+++ b/src/main/kotlin/org/openapitools/api/AddApiController.kt
@@ -44,7 +44,7 @@ class AddApiController() {
         value = ["/add"],
         consumes = ["application/json"]
     )
-    fun addPut(@Parameter(description = "", required = true) @Valid @RequestBody body: kotlin.Int): ResponseEntity<Unit> {
+    fun addPut(@Parameter(description = "", required = true) @Valid@Min(2) @RequestBody body: kotlin.Int): ResponseEntity<Unit> {
         return ResponseEntity(HttpStatus.NOT_IMPLEMENTED)

[wing328]

@lukbaran thanks for the PR, which has been merged. Can you please PM me via Slack when you've time? Thank you.

https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g