Resolve memory creep

[zivkovicmilos]

Description

This PR resolves a steady memory creep that has been noted in the Header.Copy() method.

After the fix:

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

Additional comments

Fixes EDGE-698

[codecov]

Codecov Report

Merging #668 (1e3ae91) into develop (b5462e0) will decrease coverage by 0.04%.
The diff coverage is 42.02%.

@@             Coverage Diff             @@
##           develop     #668      +/-   ##
===========================================
- Coverage    48.65%   48.61%   -0.05%     
===========================================
  Files          112      112              
  Lines        15364    15378      +14     
===========================================
  Hits          7476     7476              
- Misses        7254     7268      +14     
  Partials       634      634              

Impacted Files	Coverage Δ
blockchain/subscription.go	72.00% <ø> (ø)
blockchain/testing.go	59.29% <ø> (ø)
consensus/ibft/consensus.go	0.00% <ø> (ø)
consensus/ibft/consensus_backend.go	0.00% <0.00%> (ø)
consensus/ibft/ibft.go	4.00% <0.00%> (ø)
consensus/ibft/pos.go	0.00% <ø> (ø)
consensus/ibft/sign.go	64.58% <ø> (ø)
consensus/ibft/verifier.go	0.00% <0.00%> (ø)
contracts/staking/query.go	71.42% <ø> (ø)
jsonrpc/errors.go	41.66% <ø> (ø)
... and 24 more

📣 Codecov can now indicate which changes are the most critical in Pull Requests. Learn more

[zivkovicmilos]

@Kourin1996

Thank you for the heads up on the code simplification 🙏

Arrays are assignable by value, no need to do deep copy on them since we get that out of the box:
https://goplay.tools/snippet/wbT59SmSb0K

8f37291

[Kourin1996]

The code looks good.

[0xAleksaOpacic]

Great catch, thank you for this PR :D
I would maybe only add a unit test that covers Copy method