chore: application.yml, .gitignore 파일 수정

.gitignore

@@ -4,7 +4,6 @@ build/
 !gradle/wrapper/gradle-wrapper.jar
 !**/src/main/**/build/
 !**/src/test/**/build/
-/src/main/resources/application.yml
 
 ### STS ###
 .apt_generated

src/main/resources/application.yml

@@ -0,0 +1,21 @@
+spring:
+  datasource:
+    url: ${MYSQL_URL:jdbc:mysql://localhost}:${MYSQL_PORT:3306}/${MYSQL_SCHEMA:dev}
+    driver-class-name: com.mysql.cj.jdbc.Driver
+    username: ${MYSQL_USERNAME:root}
+    password: ${MYSQL_PASSWORD:1234}
+  jpa:
+    hibernate:
+      ddl-auto: update
+    show-sql: true
+    properties:
+      hibernate:
+        format_sql: true
+        use_sql_comments: true
+logging:
+  level:
+    org:
+      hibernate:
+        type:
+          descriptor:
+            sql: trace