imp: add tests for BuildMerklePath, make merkle path non-nullable in counterparty

[colin-axner]

Description

closes: #7121
closes: #7159

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[colin-axner]

this test fails because BuildMerklePath modifies the underlying slice elements, so despite returning a merkle path, it is also modifying the prefix passed in which might have unintentional side affects. I'm going to rework the code to avoid modifying the underlying slice of prefix

[AdityaSripal]

Nice work!!

[sonarqubecloud]

Quality Gate passed for 'ibc-go'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud