chore(deps): update dependency org.testcontainers:testcontainers to v1.20.4

Author: renovate[bot]

providers/flagd/pom.xml

@@ -141,7 +141,7 @@
         <dependency>
             <groupId>org.testcontainers</groupId>
             <artifactId>testcontainers</artifactId>
-            <version>1.20.3</version>
+            <version>1.20.4</version>
             <scope>test</scope>
         </dependency>
         <dependency>