[CHIA-3712] simplify add_transaction()

[arvidn]

Purpose:

Collapse unnecessary catching and re-throwing of exceptions.
Introduce an early exit for when we're syncing, to reduce indentation.
Replace literals with the CONSENSUS_ERROR_BAN_SECONDS constant

fixup a test for farming blocks that under-estimates the block cost prior to the hard fork (we no longer support farming blocks before the hard fork).

[coveralls-official]

Pull Request Test Coverage Report for Build 17758307913

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

• 44 of 56 (78.57%) changed or added relevant lines in 4 files are covered.
• 19 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.03%) to 91.267%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
chia/server/server.py	5	7	71.43%
chia/full_node/full_node.py	27	37	72.97%

Files with Coverage Reduction	New Missed Lines	%
chia/wallet/util/wallet_sync_utils.py	1	85.57%
chia/util/files.py	2	91.38%
chia/full_node/full_node_api.py	3	85.6%
chia/rpc/rpc_server.py	3	88.4%
chia/server/node_discovery.py	3	82.29%
chia/server/server.py	3	83.83%
chia/wallet/wallet_node.py	4	87.13%

Totals
Change from base Build 17700259666:	0.03%
Covered Lines:	102832
Relevant Lines:	112538

---

💛 - Coveralls

[github-actions]

File	Coverage	Missing Lines
chia/full_node/full_node.py	73.0%	lines 512, 514-515, 1104, 1107, 1122, 1125, 1387, 2780, 2800
chia/server/server.py	71.4%	lines 561, 564

Total	Missing	Coverage
56 lines	12 lines	78%

[wjblanke]

aok