Polish gh-2971 Adds while loop comment.

Author: spencergibb

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/filter/RemoveCachedBodyFilter.java

@@ -41,7 +41,9 @@ public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
 						log.trace("releasing cached body in exchange attribute");
 					}
 					// ensure proper release
-					while(!dataBuffer.release()) {}
+					while (!dataBuffer.release()) {
+						// release() counts down until zero, will never be infinite loop
+					}
 				}
 			}
 		});