[general] Add database test

src/test/java/icu/samnyan/aqua/FlywayTestConfig.java

@@ -0,0 +1,20 @@
+package icu.samnyan.aqua;
+
+import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * @author sam_nya (privateamusement@protonmail.com)
+ */
+@Configuration
+public class FlywayTestConfig {
+
+    @Bean
+    public FlywayMigrationStrategy clean() {
+        return flyway -> {
+            flyway.clean();
+            flyway.migrate();
+        };
+    }
+}