refactor(nocodb): remove unused functions

packages/nocodb-nest/src/meta/meta.service.ts

@@ -1042,22 +1042,10 @@ export class MetaService {
     );
   }
 
-  private isSqlite() {
-    return this.connection.clientType() === 'sqlite3';
-  }
-
   private isMssql() {
     return this.connection.clientType() === 'mssql';
   }
 
-  private isPg() {
-    return this.connection.clientType() === 'pg';
-  }
-
-  private isSnowflake() {
-    return this.connection.clientType() === 'snowflake';
-  }
-
   private now(): any {
     if (this.isMySQL()) {
       return dayjs().utc().format('YYYY-MM-DD HH:mm:ss');