Fix struct references. Version bump to v0.0.43

[slundqui]

Fixes an issue where struct references don't get matched up correctly. See new struct_references test that highlights this issue.

• When finding what type files to import when building type files (for struct references in other files), we look at the contract name of structs instead of looking for structs in abis.
• Always reference a fully qualified name for nested structs. This solves issues around creating the return type data structure when doing function.call().
• Define the python type as the fully qualified name. This solves an issue with structures in different file references and functions returning a vector of the struct.
• Handle the case when a struct doesn't get referenced with a contract name in the abi.
• Fix to handling of struct arrays as input/output to functions with fully qualified names for structs.

This might solve https://github.com/delvtech/pypechain/issues/98

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 71.77914% with 46 lines in your changes missing coverage. Please review.

Project coverage is 71.57%. Comparing base (67cde22) to head (f83986d).

Files with missing lines	Patch %	Lines
pypechain/utilities/abi.py	16.66%	10 Missing :warning:
.../test/struct_references/types/ContractCContract.py	87.50%	8 Missing :warning:
pypechain/render/contract.py	0.00%	7 Missing :warning:
pypechain/render/types.py	0.00%	7 Missing :warning:
pypechain/test/structs/types/StructsAContract.py	25.00%	6 Missing :warning:
pypechain/test/structs/types/StructsCContract.py	33.33%	4 Missing :warning:
pypechain/test/structs/types/StructsBContract.py	33.33%	2 Missing :warning:
pypechain/utilities/types.py	0.00%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #135 +/- ## ========================================== + Coverage 71.22% 71.57% +0.35% ========================================== Files 50 55 +5 Lines 2318 2417 +99 ========================================== + Hits 1651 1730 +79 - Misses 667 687 +20 ``` | [Flag](https://app.codecov.io/gh/delvtech/pypechain/pull/135/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/delvtech/pypechain/pull/135/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech) | `71.57% <71.77%> (+0.35%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech#carryforward-flags-in-the-pull-request-comment) to find out more.

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.