mundayweb.com itself does not collect any personal information.
If you have an account at boinc.mundayweb.com your e-mail address is saved by the site in order to provide BOINC stats services.
In addition your BOINC stats from the projects you have chosen are also saved by the site. You can control if your BOINC stats are made available to sites such as boinc.mundayweb.com by editing your GDPR settings etc. in the accounts for your BOINC projects. Please visit the relevant BOINC project’s homepage.