[Forwardport] Fix Issue 15679 : max length varchar

[julienanquetil]

Original Pull Request

#15835

Description

Update the const DB_MAX_VARCHAR_LENGTH to allow 1024 char instead of 256

Fixed Issues (if relevant)

1. Attribute image exceeded max length in row(s) when importing images from Amazon.com with CSV file #15679: Attribute image exceeded max length

Manual testing scenarios

1. import a file with content of base_image column is:
   https://images-na.ssl-images-amazon.com/images/I/61btlFPdvBL._SL1000_.jpg,https://images-na.ssl-images-amazon.com/images/I/51I%2Bhf88F7L._SL1000_.jpg,https://images-na.ssl-images-amazon.com/images/I/51y0P8C5-2L._SL1000_.jpg,https://images-na.ssl-images-amazon.com/images/I/51uwDQfaHrL._SL1000_.jpg,https://images-na.ssl-images-amazon.com/images/I/61Wh7FkyNYL._SL1000_.jpg
2. ...

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[dmanners]

Since the original PR is now closed I will close this one as well. As always feel free to re-open when you have had sometime to make progress on this.

Thanks