support gitlab oauth2 login (#28)

* feat: support gitlab oauth login

* feat: change appType to enum

dao/src/main/java/com/databasir/dao/converter/OAuthAppTypeConverter.java

@@ -0,0 +1,12 @@
+package com.databasir.dao.converter;
+
+import com.databasir.dao.enums.OAuthAppType;
+import org.jooq.impl.EnumConverter;
+
+public class OAuthAppTypeConverter extends EnumConverter<String, OAuthAppType> {
+
+    public OAuthAppTypeConverter() {
+        super(String.class, OAuthAppType.class);
+    }
+
+}