Issues with repo signatures.

It seems that SHA1 has been used to sign the repo. It has been recently dropped by APT. At least changing it to SHA256 would a good option.

This is the error message:

W: http://es.archive.trisquel.info/trisquel/dists/flidas/InRelease: Signature by key E6C27099CA21965B734AEA31B4EFB9F38D8AEBF1 uses weak digest algorithm (SHA1)
W: http://es.archive.trisquel.info/trisquel/dists/flidas-updates/InRelease: Signature by key E6C27099CA21965B734AEA31B4EFB9F38D8AEBF1 uses weak digest algorithm (SHA1)
W: http://es.archive.trisquel.info/trisquel/dists/flidas-security/InRelease: Signature by key E6C27099CA21965B734AEA31B4EFB9F38D8AEBF1 uses weak digest algorithm (SHA1)