Rust wrapper: fix ECCPoint import_der_ex unit tests

[holtrop]

Description

Rust wrapper: fix ECCPoint import_der_ex unit tests

Testing

CI tests for 64-bit and 32-bit targets

Checklist

• [ ] added tests
• [ ] updated/added doxygen
• [ ] updated appropriate READMEs
• [ ] Updated manual and documentation

[holtrop]

retest this please

org.jenkinsci.plugins.workflow.support.steps.AgentOfflineException: Unable to create live FilePath for wolf-linux-cloud-node-t9d9xr; wolf-linux-cloud-node-t9d9xr was marked offline: Connection was broken