Bump justnimbus to 0.7.4

[kvanzuijlen]

Proposed change

This PR bumps justnimbus to 0.7.4 as requested by @joostlek in kvanzuijlen/justnimbus#6. Full diff: kvanzuijlen/justnimbus@0.7.3...0.7.4

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
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[epenet]

LGTM 👍