Update dependency org.testcontainers:postgresql to v1.20.3 (#59)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

postgres-cdc/build.gradle

@@ -17,7 +17,7 @@ testing {
     suites {
         test {
             dependencies {
-                implementation("org.testcontainers:postgresql:1.20.2")
+                implementation("org.testcontainers:postgresql:1.20.3")
                 implementation("org.assertj:assertj-core:3.26.3")
                 implementation("org.flywaydb:flyway-core:9.22.3")
                 implementation("org.awaitility:awaitility:4.2.2")