Update dependency org.testcontainers:testcontainers to v1.21.1

Author: renovate[bot]

gradle/versions.gradle

@@ -186,7 +186,7 @@ dependencyManagement {
 
     dependency 'org.springframework.security:spring-security-crypto:5.7.2'
 
-    dependency 'org.testcontainers:testcontainers:1.17.2'
+    dependency 'org.testcontainers:testcontainers:1.21.1'
 
     dependency 'org.web3j:quorum:4.9.0'
     dependencySet(group: 'org.web3j', version: '4.9.4') {