Fix/reminder default scheduling time

[jungwire]

Negotiator pull request:

Description:

Changes the default schedule of the reminder emails from every night to Monday midnight

Checklist:

Make sure you tick all the boxes bellow if they are true or do not apply:

• [x] I have performed a self review of my code
• [x] My code follows Google Java Code style
• [x] I have made my code as simple as possible
• [x] I have added unit tests and the code coverage has not decreased
• [x] I have updated the documentation in all relevant places

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 79.71%. Comparing base (c760e7a) to head (7a61f85).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #320 +/- ## ========================================= Coverage 79.71% 79.71% Complexity 1076 1076 ========================================= Files 146 146 Lines 3243 3243 Branches 173 173 ========================================= Hits 2585 2585 Misses 543 543 Partials 115 115 ``` | [Flag](https://app.codecov.io/gh/BBMRI-ERIC/negotiator/pull/320/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=BBMRI-ERIC) | Coverage Δ | | |---|---|---| | [unit](https://app.codecov.io/gh/BBMRI-ERIC/negotiator/pull/320/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=BBMRI-ERIC) | `79.71% <ø> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=BBMRI-ERIC#carryforward-flags-in-the-pull-request-comment) to find out more.

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