Stats: Number of unit admins

[i-oden]

Before submitting this PR

1. Description: Save number of unit admins to database, in the Reporting table.
2. Jira task / GitHub issue: DDS-1551
3. How to test:
   1. In the dds_web container, run flask db upgrade and flask db downgrade to verify the migrations.
   2. After one flask db downgrade, add a row manually to the Reporting table, and then run flask db upgrade. There should be no errors.
4. Type of change: Check the relevant boxes in the section below
5. Add docstrings and comments to code, even if you personally think it's obvious.

What type of change(s) does the PR contain?

• New feature
  • Breaking: Please describe the reason for the break and how we can fix it.
  • Non-breaking
• Database change
  • Migration included in PR
  • Migration not needed
• Bug fix
  • Breaking: Please describe the reason for the break and how we can fix it.
  • Non-breaking
• Security Alert fix
• Documentation
• Tests (only)
• Workflow

Checklist

• Sprintlog
  • Added
  • Not needed (E.g. PR contains only tests)
• Rebase / Update / Merge from base branch (the branch from which the current is forked)
  • Done
  • Not needed
• Blocking PRs
  • Merged
  • No blocking PRs
• PR to master branch
  • Yes: Read the release instructions
    • I have followed steps 1-7.
  • No

Actions / Scans

• Black: Python code formatter. Does not execute. Only tests.
  Run black . locally to execute formatting.
  • Passed
• Prettier: General code formatter. Our use case: MD and yaml mainly.
  Run npx prettier --write . locally to execute formatting.
  • Passed
• Yamllint: Linting of yaml files.
  • Passed
• Tests: Pytest to verify that functionality works as expected.
  • New tests added
  • No new tests
  • Passed
• CodeQL: Scan for security vulnerabilities, bugs, errors
  • New alerts: Go through them and either fix, dismiss och ignore. Add reasoning in items below.
  • Alerts fixed: What?
  • Alerts ignored / dismissed: Why?
  • Passed
• Trivy: Security scanner
  • New alerts: Go through them and either fix, dismiss och ignore. Add reasoning in items below.
  • Alerts fixed: What?
  • Alerts ignored / dismissed: Why?
  • Passed
• Snyk: Security scanner
  • New alerts: Go through them and either fix, dismiss och ignore. Add reasoning in items below.
  • Alerts fixed: What?
  • Alerts ignored / dismissed: Why?
  • Passed

[i-oden]

@valyo This one is ready now, tests are fixed

[valyo]

Everything seems fine but following "Hot to test" doesn't behave as expected (or I am not doing it corretly)

[i-oden]

Everything seems fine but following "Hot to test" doesn't behave as expected (or I am not doing it corretly)

How does it behave?

[valyo]

Actually it does