feat: add block height to get-transaction RPC

[hstove-stacks]

When you call /v3/transaction/:txid, you get the block's index block hash, but there still isn't an easy way to know if that block is canonical or not. Because this RPC was added for the purpose of indexers who are using this to determine the validity of a given transaction, it seems like adding this field to the response is the best option.

There are two new fields:

• block_height: Some(u64), if the tx is canonical, this is the height of the block it was in
• is_canonical: equivalent to block_height.is_some()

[codecov]

Codecov Report

❌ Patch coverage is 35.00000% with 26 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.86%. Comparing base (7ff75a2) to head (fa330e7).
⚠️ Report is 2 commits behind head on develop.

Files with missing lines	Patch %	Lines
stacks-node/src/tests/signer/v0.rs	0.00%	24 Missing ⚠️
stackslib/src/net/api/gettransaction.rs	87.50%	2 Missing ⚠️

❌ Your project check has failed because the head coverage (75.86%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6733      +/-   ##
===========================================
+ Coverage    70.05%   75.86%   +5.80%     
===========================================
  Files          578      578              
  Lines       358373   358408      +35     
===========================================
+ Hits        251064   271892   +20828     
+ Misses      107309    86516   -20793     

Files with missing lines	Coverage Δ
stackslib/src/net/api/gettransaction.rs	90.26% <87.50%> (+4.40%)	⬆️
stacks-node/src/tests/signer/v0.rs	36.36% <0.00%> (+6.49%)	⬆️

... and 363 files with indirect coverage changes

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