Stats: TBhours in last month

[i-oden]

Before submitting this PR

1. Description: Calculate and save number of TB hours used during the last month.
2. Jira task / GitHub issue: DDS-1560
3. How to test: Add information on how someone could manually test this functionality. As detailed as possible.
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

[valyo]

Looks good, just minor comments on the two comments

[i-oden]

Looks good, just minor comments on the two comments

@valyo 👍🏻 Fixed!