Update dependency org.junit:junit-bom to v5.9.3 (#47)

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

build.gradle.kts

@@ -42,7 +42,7 @@ dependencies {
     }
 
     // unit testing
-    testImplementation(platform("org.junit:junit-bom:5.9.2"))
+    testImplementation(platform("org.junit:junit-bom:5.9.3"))
     testImplementation("org.junit.jupiter", "junit-jupiter")
     testImplementation("org.mockito", "mockito-core", "3.+")
 }