Met.no - only update data if coordinates changed

[Danielhiversen]

Breaking change

Proposed change

Only update the component if the config has changed.
EVENT_CORE_CONFIG_UPDATE is fired twice during startup, so currently, the component is updated three times during startup for the home entity.
Related to #48730

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• Dependency upgrade
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[probot-home-assistant]

Hey there @thimic, mind taking a look at this pull request as its been labeled with an integration (met) you are listed as a codeowner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[MartinHjelmare]

Looks good! Would be good to add a test for the missing coverage.

[MartinHjelmare]

Thanks!