Fix rainforest eagle incorrectly fetch conncted first try

[balloob]

Breaking change

Proposed change

The first time is_connected is not populated and can raise. This prevents that and only fetches is_connected from the meter if data has been fetched once.

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)
• 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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[probot-home-assistant]

Hey there @gtdiehl, @jcalbert, mind taking a look at this pull request as it has been labeled with an integration (rainforest_eagle) you are listed as a code owner for? Thanks!
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[frenck]

Rebased the PR to deal with the CI issue