fix: avoid interference from rust tests during IDL generation

[losman0s]

Problem

The test result/summary line from cargo test is used as delimiter to assign the content of the different IDL sections to the final idl variable. However that delimiter check is currently too loose and leads to some of the IDL sections being wiped when rust tests are present in the program crate.

Solution

This PR tightens the delimiter check to exclude other test results from wiping those sections.

[vercel[bot]]

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[losman0s]

Thanks! Could you note this fix in the CHANGELOG?

Done