chore(deps): update dependency org.postgresql:postgresql to v42.7.8

Author: renovate[bot]

build.gradle

@@ -39,7 +39,7 @@ dependencies {
     testImplementation 'org.springframework.boot:spring-boot-starter-jdbc:2.3.5.RELEASE'
     testImplementation 'org.springframework.boot:spring-boot-starter-test:2.3.5.RELEASE'
 
-    testImplementation 'org.postgresql:postgresql:42.2.5'
+    testImplementation 'org.postgresql:postgresql:42.7.8'
 
     testCompile "org.testcontainers:spock:1.15.2"
     testCompile "org.testcontainers:postgresql:1.15.2"