chore: modify id type to use varchar

Author: SHACRAM

src/main/resources/db/migration/V1__Create_tables_User_and_Station.sql

@@ -1,9 +1,9 @@
 CREATE TABLE users (
-    id SERIAL PRIMARY KEY,
-    email VARCHAR(50) NOT NULL,
-    password VARCHAR(200) NOT NULL,
-    status VARCHAR(20) NOT NULL,
-    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+   id VARCHAR(40) PRIMARY KEY,
+   email VARCHAR(50) NOT NULL,
+   password VARCHAR(200) NOT NULL,
+   status VARCHAR(20) NOT NULL,
+   created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
 );
 
 CREATE TABLE station (