Simplify gen_and_send_sb and make it type safe

[AmineKhaldi]

No description provided.

[coveralls-official]

Pull Request Test Coverage Report for Build 8819108904

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 18 of 18 (100.0%) changed or added relevant lines in 1 file are covered.
• 11 unchanged lines in 5 files lost coverage.
• Overall coverage increased (+0.008%) to 91.103%

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Files with Coverage Reduction	New Missed Lines	%
chia/rpc/rpc_server.py	1	89.0%
chia/wallet/wallet_node.py	1	88.64%
chia/data_layer/data_layer.py	1	84.4%
chia/server/node_discovery.py	4	79.08%
chia/full_node/full_node.py	4	84.81%

Totals
Change from base Build 8809423530:	0.008%
Covered Lines:	98689
Relevant Lines:	108299

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💛 - Coveralls