Check typing in all SDK extensions

[seherv]

Merging all the extensions code into the core SDK package means mypy has more code to type check now.

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Acceptance criteria:

• Temporary type: ignore marks are removed
• SDK core passes type checks
• SDK extensions passes type checks

[seherv]

Please re-tag this as kind/maintenance 😅

[dapr-bot]

This issue has been automatically marked as stale because it has not had activity in the last 60 days. It will be closed in the next 7 days unless it is tagged (pinned, good first issue, help wanted or triaged/resolved) or other activity occurs. Thank you for your contributions.