Change utility_meter log level for invalid old state

[ollo69]

Proposed change

The warning log that warn about an invalid old state in the utility meter seems excessive and is normally logged when HA is started and state from the source sensor is still unavailable or unknown. I propose to lower this log to debug level. Warning log about invalid new state is available few row above.

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[home-assistant]

Hey there @dgomes, mind taking a look at this pull request as it has been labeled with an integration (utility_meter) you are listed as a code owner for? Thanks!

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[epenet]

Is this still needed after merge of #91035 and/or #92825?

[ollo69]

I think yes, because all that checks in PRs are related to current state but the warning is related to old state. So when current state is valid it tries to calculate the difference, but because the old state is something like UNKNOWN or UNAVAILABLE generate the warning.

[dgomes]

People seam to care more about the warning message then the root cause of the warning message, so yes... I'm tempted to accept this PR

[ollo69]

@dgomes,

I can agree with you, the point is that a warning should indicate a potential issue, and in this case this is not a real issue. Not everybody have the capacity to analyze the code, so if they receive a warning just warn 🤔.
As alternative solution we could add additional check for specific situation, but probably in this case is more simple to just reduce the log level.

[emontnemery]

Let's try this to decrease log spam. If debug is too low, we can adjust the severity again 👍