public Resource getTrustCertCollection() {
            return this.trustCertCollection;
        }
Gets the resource containing the the trusted certificate collection. If {@code null} or empty the use the
system's default collection should be used.

@return The trusted certificate collection resource or null.

@see #setTrustCertCollection(Resource)
grpc-client-spring-boot-starter/src/main/java/net/devh/boot/grpc/client/config/GrpcChannelProperties.java